Depositing layers in OLED devices using viscous flow

ABSTRACT

A method of depositing a patterned organic layer includes providing a manifold and an OLED display substrate in a chamber at reduced pressure and spaced relative to each other; providing a structure sealingly covering at least one surface of the manifold, the structure including a plurality of nozzles extending through the structure into the manifold. The method also includes delivering vaporized organic materials into the manifold, and applying an inert gas under pressure into the manifold so that the inert gas provides a viscous gas flow through each of the nozzles, such viscous gas flow transporting at least portions of the vaporized organic materials from the manifold through the nozzles to provide directed beams of the inert gas and of the vaporized organic materials and projecting the directed beams onto the OLED display substrate for depositing a pattern of an organic layer on the substrate.

CROSS REFERENCE TO RELATED APPLICATIONS

Reference is made to commonly assigned U.S. patent application Ser. No.10/252,639 filed Sep. 23, 2002 now U.S. Pat. No. 6,911,671 by Michael A.Marcus et al., entitled “Device for Depositing Patterned Layers in OLEDDisplays”, the disclosure of which is herein incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to forming patterned organic layers inmaking a multicolor OLED display or full-color OLED display, and moreparticularly to vapor depositing such patterned layers without requiringprecision shadow masks.

BACKGROUND OF THE INVENTION

An organic light-emitting diode (OLED) device, also referred to as anorganic electroluminescent device, can be constructed by sandwiching twoor more organic layers between first and second electrodes.

In single-color OLED devices or displays, also called monochrome OLEDs,these organic layers are not patterned but are formed as continuouslayers.

In multicolor OLED devices or displays or in full-color OLED displays,an organic hole-injecting and hole-transporting layer is formed as acontinuous layer over and between the first electrodes. A pattern of oneor more laterally adjacent organic light-emitting layers are then formedover the continuous hole-injecting and hole-transporting layer. Thispattern, and the organic materials used to form the pattern, is selectedto provide multicolor or full-color light-emission from a completed andoperative OLED display in response to electrical potential signalsapplied between the first and second electrodes.

An unpatterned organic electron-injecting and electron-transportinglayer is formed over the patterned light-emitting layers, and one ormore second electrodes are provided over this latter organic layer.

Providing a patterned organic light-emitting layer capable of emittinglight of two different colors (multicolor) or of three different colors,for example, the primary colors of red (R), green (G), and blue (B), isalso referred to as color pixelation since the pattern is aligned withpixels of an OLED display. The RGB pattern provides a full-color OLEDdisplay.

Various processes have been proposed to achieve color pixelation in OLEDimaging panels. For example, Tang et al. in commonly assigned U.S. Pat.No. 5,294,869 discloses a process for the fabrication of a multicolorOLED imaging panel using a shadow masking method in which sets ofpillars or walls made of electrically insulative materials form anintegral part of the device structure. A multicolor organicelectroluminescent (“EL”) medium is vapor deposited and patterned bycontrolling an angular position of a substrate with respect to adeposition vapor stream. The complexity of this process resides in therequirements that the integral shadow mask have multilevel topologicalfeatures, which may be difficult to produce, and that angularpositioning of the substrate with respect to one or more vapor sourcesmust be controlled.

Littman et al. in commonly assigned U.S. Pat. No. 5,688,551 recognizedthe complexity of the above described Tang et al. process, and disclosesa method of forming a multicolor organic EL display panel in which aclose-spaced deposition technique is used to form a separately coloredorganic EL medium on a substrate by patternwise transferring the organicEL medium from a donor sheet to the substrate. The donor sheet includesa radiation-absorbing layer which can be unpatterned or which can beprepatterned in correspondence with a pattern of pixels or subpixels onthe substrate. The donor sheet has to be positioned either in directcontact with a surface of the substrate or at a controlled relativelysmall distance from the substrate surface to minimize the undesirableeffect of divergence of the EL medium vapors issuing from the donorsheet upon heating the radiation-absorbing layer.

In general, positioning an element such as, for example, a donor sheetor a mask, in direct contact with a surface of a substrate can inviteproblems of abrasion, distortion, or partial lifting of a relativelythin and mechanically fragile organic layer which has been formedpreviously on the substrate surface. For example, an organichole-injecting and hole-transporting layer may be formed over thesubstrate prior to deposition of a first-color pattern. In depositing asecond-color pattern, direct contact of a donor sheet or a mask with thefirst-color pattern may cause abrasion, distortion, or partial liftingof the first-color pattern.

Positioning a donor sheet or a mask at a controlled distance from thesubstrate surface may require incorporation of spacer elements on thesubstrate, or on the donor sheet or the mask, or on the substrate and onthe donor sheet. Alternatively, special fixtures may have to be devisedto provide for a controlled spacing between the substrate surface and adonor sheet or a mask.

The potential problems or constraints also apply to disclosures byGrande et al. in commonly assigned U.S. Pat. No. 5,871,709 whichdescribes a method for patterning high-resolution organic EL displays,as well as to teachings by Nagayama et al. in U.S. Pat. No. 5,742,129which discloses the use of shadow masking in manufacturing an organic ELdisplay panel.

The above described potential problems or constraints are overcome bydisclosures of Tang et al. in commonly assigned U.S. Pat. No. 6,066,357which teaches methods of making a full-color OLED display. The methodsinclude ink-jet printing of fluorescent dopants selected to produce red,green, or blue light emission from designated subpixels of the display.The dopants are printed sequentially from ink-jet printing compositionswhich permit printing of dopant layers over an organic light-emittinglayer containing a host material selected to provide host light emissionin a blue spectral region. The dopants are diffused from the dopantlayer into the light-emitting layer.

The ink-jet printing of dopants does not require masks, and surfaces ofink-jet print heads are not contacting a surface of the organiclight-emitting layer. However, the ink-jet printing of dopants isperformed under ambient conditions in which oxygen and moisture in theambient air can result in partial oxidative decomposition of theuniformly deposited organic light-emitting layer containing the hostmaterial. Additionally, direct diffusion of a dopant, or subsequentdiffusion of a dopant, into the light-emitting layer can cause partialswelling and attendant distortion of the domains of the light-emittinglayer into which the dopant was diffused.

OLED imaging displays can be constructed in the form of so-calledpassive matrix devices or in the form of so-called active matrixdevices.

In a passive matrix OLED display of conventional construction, aplurality of laterally spaced light-transmissive anodes, for example,indium-tin-oxide (ITO) anodes are formed as first electrodes on alight-transmissive substrate such as, for example, a glass substrate.Three or more organic layers are then formed successively by vapordeposition of respective organic materials from respective vaporsources, within a chamber held at reduced pressure, typically less than10⁻³ Torr (1.33×10⁻¹ Pa). A plurality of laterally spaced cathodes isdeposited as second electrodes over an uppermost one of the organiclayers. The cathodes are oriented at an angle, typically at a rightangle, with respect to the anodes.

Such conventional passive matrix OLED displays are operated by applyingan electrical potential (also referred to as a drive voltage) between anindividual row (cathode) and, sequentially, each column (anode). When acathode is biased negatively with respect to an anode, light is emittedfrom a pixel defined by an overlap area of the cathode and the anode,and emitted light reaches an observer through the anode and thesubstrate.

In an active matrix OLED display, an array of sets of thin-filmtransistors (TFTs) is provided on a light-transmissive substrate suchas, for example, a glass substrate. One TFT, respectively, of each ofthe sets of TFTs is connected to a corresponding light-transmissiveanode pad, which can be made, for example, of indium-tin-oxide (ITO).Three or more organic layers are then formed successively by vapordeposition in a manner substantially equivalent to the construction ofthe aforementioned passive matrix OLED display. A common cathode isdeposited as a second electrode over an uppermost one of the organiclayers. The construction and function of an active matrix OLED displayis described in commonly assigned U.S. Pat. No. 5,550,066.

In order to provide a multicolor or a full-color (red, green, and bluesubpixels) passive matrix or active matrix OLED display, colorpixelation of at least portions of an organic light-emitting layer isrequired.

Color pixelation of OLED displays can be achieved through variousmethods as detailed above. One of the most common current methods ofcolor pixelation integrates the use of one or more of the describedvapor sources and a precision shadow mask temporarily fixed in referenceto a device substrate. Organic light-emitting material, such as thatused to create an OLED emitting layer, is sublimed from a source (orfrom multiple sources) and deposited on the OLED substrate through theopen areas of the aligned precision shadow mask. This physical vapordeposition (PVD) for OLED production is achieved in vacuum through theuse of a heated vapor source containing vaporizable organic OLEDmaterial. The organic material in the vapor source is heated to attainsufficient vapor pressure to effect efficient sublimation of the organicmaterial, creating a vaporous organic material plume that travels to anddeposits on an OLED substrate. A variety of vapor sources based ondifferent operating principles exist, including the so-called pointsources (heated small sublimation cross-sectional area sources) andlinear sources (sources of large sublimation cross-sectional area).Multiple mask-substrate alignments and vapor depositions are used todeposit a pattern of differing light-emitting layers on desiredsubstrate pixel areas or subpixel areas creating, for example, a desiredpattern of red, green, and blue pixels or subpixels on an OLEDsubstrate. Note that in this method which is commonly used in OLEDproduction not all of the vaporized material present in the vaporousmaterial plume is deposited onto desired areas of the substrate. Insteadmuch of the material plume is deposited onto various vacuum chamberwalls, shielding, and precision shadow masks. This leads to poormaterial utilization factors and consequently high materials cost.

While precision shadow masking is a feasible method for OLED production,it also effects many complications and potential predicaments to displaymanufacturing. First, care must be taken in positioning and removingthese masks onto and from a device substrate to avoid physical damage toOLED devices. Second, when vacuum depositing large area substrates it isdifficult to keep shadow masks in intimate contact at all places alongthe length of the substrate, which can lead to unfocussed depositions ormask induced substrate physical damage. Third, when vacuum depositingthree colored regions at different locations on the substrate, threesets of precision shadow masks may be needed and can cause unwanteddelays in OLED production. Fourth, keeping mask to substrate precisionalignment with the required accuracy along the length of largesubstrates is very difficult for several reasons, including mask andsubstrate thermal expansion mismatches, small pixel pitches, and maskfabrication limitations. Also, when vacuum depositing multiplesubstrates during a single vacuum pump down cycle, material residue canbuild up on shadow masks and can eventually cause defects to form in thepixels being deposited.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a method of colorpixelating an organic layer in making a multicolor or a full-colororganic electroluminescent (EL) display.

It is another object of the present invention to provide a method ofdepositing in a pattern an organic layer onto an OLED display substrate.

It is a further object of the present invention to provide a method ofcolor pixelating an organic layer which overcomes the constraints ofprior art and of currently used methods of color pixelation in making amulticolor or a full-color organic electroluminescent (EL) display.

In one aspect, these objects are achieved by a method of depositing in apattern an organic layer onto an OLED display substrate, comprising thesteps of:

a) providing a manifold and an OLED display substrate in a chamber atreduced pressure and spaced relative to each other;

b) providing a structure sealingly covering one surface of the manifold,the structure including a plurality of nozzles extending through thestructure into the manifold, and the nozzles being spaced from eachother in correspondence with the pattern to be deposited onto the OLEDdisplay substrate;

c) orienting the OLED display substrate with respect to the nozzles inthe structure;

d) delivering vaporized organic materials into the manifold; and

e) applying an inert gas under pressure into the manifold so that theinert gas provides a viscous gas flow through each of the nozzles, suchviscous gas flow transporting at least portions of the vaporized organicmaterials from the manifold through the nozzles to provide directedbeams of the inert gas and of the vaporized organic materials andprojecting the directed beams onto the OLED display substrate fordepositing a pattern of an organic layer on the substrate.

In another aspect, these objects are achieved by a method ofconcurrently depositing in a three-color pattern an organic layer ontoan OLED display substrate, comprising the steps of:

a) providing a manifold assembly and an OLED display substrate in achamber at reduced pressure and spaced relative to each other, themanifold assembly including a first manifold, a second manifold, and athird manifold;

b) providing a separate structure sealingly covering one surface of eachone of the first, second, and third manifolds, each separate structureincluding a plurality of nozzles extending through each structure into acorresponding manifold, and the nozzles in each separate structure beingspaced from each other in correspondence with the three-color pattern tobe deposited onto the OLED display substrate;

c) orienting the OLED display substrate with respect to the nozzles inone of the separate structures;

d) delivering concurrently first-color forming vaporized organicmaterials into the first manifold, second-color forming vaporizedorganic materials into the second manifold, and third-color formingvaporized organic materials into the third manifold assembly; and

e) applying an inert gas under pressure concurrently into each one ofthe first, second, and third manifolds so that the inert gas provides aviscous gas flow through each of the plurality of nozzles in each of theseparate structures, such viscous gas flow transporting concurrently atleast portions of the first-color forming, second-color forming, andthird-color forming vaporized organic materials from a respectivelycorresponding manifold through corresponding nozzles to provide directedbeams of the inert gas and of the first-color forming, second-colorforming, and third-color forming vaporized organic light-emittingmaterials and projecting the directed beams onto the OLED displaysubstrate for concurrently depositing a three-color pattern on thesubstrate.

In a still further aspect, the present invention is directed to a methodof depositing in a pattern vaporized material onto a surface, comprisingthe steps of:

a) providing vaporized material in a manifold of reduced pressure;

b) providing a structure sealingly covering one surface of the manifold,the structure including a plurality of nozzles extending through thestructure into the manifold, and the nozzles being spaced from eachother in correspondence with the pattern to be deposited onto thesurface; and

c) applying an inert gas under pressure into the manifold so that theinert gas provides a viscous gas flow through each of the nozzles, suchviscous gas flow transporting at least portions of the vaporizedmaterial from the manifold through the nozzles to provide directed beamsof the inert gas and of the vaporized material and projecting thedirected beams onto the surface upon which deposition is desired.

ADVANTAGES

A feature of the present invention is that the method of colorpixelating an organic layer uses directed vapor beams of organicmaterials.

Another feature of the present invention is that the method of colorpixelating an organic layer is effected in a chamber at reduced pressureand in the presence of an inert gas.

Another feature of the present invention is that the method of colorpixelating an organic layer permits concurrent three-color patternwisedeposition onto an OLED display substrate.

Another feature of the present invention is that the method of colorpixelating an organic layer includes providing a plurality of vaporsources disposed outside of a deposition chamber for generating vaporsof organic materials, and connecting such vapor sources to a manifolddisposed in the chamber.

Another feature of the present invention is that the method of colorpixelating does not require the use of precision shadowmasks or masking.

Another feature of the present invention is that it enables thepotential to coat mixtures of many different materials in a singledeposited layer.

Another feature of the present invention is that the method ofdeposition allows very high material utilization factors, as allsublimed material is directed and deposited directly onto the desiredpixel areas on the substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view of a passive matrix OLED displayhaving partially peeled-back elements to reveal various layers;

FIG. 2 is a schematic perspective view of an OLED apparatus suitable formaking a relatively large number of OLED displays and having a pluralityof stations extending from hubs;

FIG. 3 is a schematic section view of a carrier containing a relativelylarge number of substrates or structures, and positioned in a loadstation of the apparatus of FIG. 2 as indicated by section lines 3—3 inFIG. 2;

FIG. 4 is a schematic top view of a full-color (RGB) passive matrix OLEDdisplay that can be color pixelated by the method of the presentinvention;

FIG. 5 is a schematic sectional view of the OLED display, taken alongthe section lines 5—5 of FIG. 4;

FIG. 6 is a circuit diagram of repeating units of a portion of an activematrix OLED display;

FIG. 7 is a schematic sectional view of an active matrix OLED displayhaving RGB color pixelation of the light-emitting layer which can beformed by the method of the present invention;

FIG. 8 is a schematic rendition of a vapor deposition apparatus by whichthe present invention can be practiced, and including a chamber in whichare disposed a substrate and a manifold having a structure or nozzleplate covering the manifold and including nozzles for producing directedvapor beams, and a plurality of vapor sources and an inert gas supplydisposed outside of the chamber and connected to the manifold;

FIG. 9 shows a structure or nozzle plate having nozzles arranged along acenter line;

FIG. 10 is a sectional view of the nozzle plate, taken along lines 10—10of FIG. 9, and defining a nozzle length dimension and a nozzle insidedimension;

FIG. 11 shows a nozzle plate having a two-dimensional array of nozzlesarranged in rows and columns;

FIG. 12 is a schematic top view of a cylindrical tubular manifold havingnozzles arranged along a center line;

FIG. 13 is a sectional view of the cylindrical tubular manifold, takenalong section lines 13—13 of FIG. 12, and defining a nozzle lengthdimension and a nozzle inside dimension;

FIG. 13A is a sectional view of a modified cylindrical tubular manifoldhaving a curved nozzle plate disposed over a slit-shaped aperture formedin a cylindrical manifold housing;

FIG. 14 indicates schematically a relationship between divergence of anorganic material vapor stream issuing from a nozzle over a manifold and,respectively, a vapor pressure in the manifold and the vapor pressureplus inert gas pressure levels in the manifold;

FIG. 15 is a sectional view of an embodiment of a vapor source such asthe vapor sources shown schematically in FIG. 8;

FIG. 16 is a schematic sectional view of the LEL vapor depositionstation of FIG. 2, and indicating motion of the substrate from a firstposition, over and past the nozzles, and into a second position;

FIG. 17 is a schematic top view of a portion of the LEL vapor depositionstation of FIG. 2, and showing alignment features on the nozzle plateand on the substrate holder, and an indexing feature of indexing thesubstrate in a y-direction prior to each substrate motion in anx-direction over and past the nozzles; and

FIG. 18 shows schematically a manifold assembly, which is useful forconcurrent color pixelation of an RGB full-color organic light-emittinglayer in a single pass of a substrate over and past the nozzles in theassembly.

DETAILED DESCRIPTION OF THE INVENTION

The drawings are necessarily of a schematic nature since layer thicknessdimensions of OLEDs are frequently in the sub-micrometer ranges, whilefeatures representing lateral device dimensions can be in a range of25–2000 millimeter. Furthermore, the plurality of nozzles formed in thenozzle plate(s) or structure(s) is relatively small in size whencompared to a length dimension over which the nozzles extend.Accordingly, the drawings are scaled for ease of visualization ratherthan for dimensional accuracy.

The term “display” or “display panel” is employed to designate a screencapable of electronically displaying video images or text. The term“pixel” is employed in its art-recognized usage to designate an area ofa display panel that can be stimulated to emit light independently ofother areas. The term “multicolor” is employed to describe a displaypanel that is capable of emitting light of a different hue in differentareas. In particular, it is employed to describe a display panel that iscapable of displaying images of different colors. These areas are notnecessarily contiguous. The term “full color” is employed to describemulticolor display panels that are capable of emitting in the red,green, and blue regions of the visible spectrum and displaying images inany combination of hues. The red, green, and blue colors constitute thethree primary colors from which all other colors can be generated byappropriately mixing these three primaries. The term “hue” refers to theintensity profile of light emission within the visible spectrum, withdifferent hues exhibiting visually discernible differences in color. Thepixel or subpixel is generally used to designate the smallestaddressable unit in a display panel. For a monochrome display, there isno distinction between pixel or subpixel. The term “subpixel” is used inmulticolor display panels and is employed to designate any portion of apixel that can be independently addressable to emit a specific color.For example, a blue subpixel is that portion of a pixel that can beaddressed to emit blue light. In a full-color display, a pixel generallycomprises three primary color subpixels, namely red, green, and blue,frequently abbreviated to “RGB”. The term “pitch” is used to designatethe distance separating two pixels or subpixels in a display panel.Thus, a subpixel pitch means the separation between two subpixels. Theterm “inert gas” denotes a gas, which is chemically non-reactive towardorganic vapors and toward organic layers formed on OLED displaysubstrates.

Turning to FIG. 1, a schematic perspective view of a passive matrix OLEDdisplay 10 is shown having partially peeled-back elements to revealvarious layers.

A light-transmissive substrate 11 has formed thereon a plurality oflaterally spaced first electrodes 12 (also referred to as anodes). Anorganic hole-transporting layer (HTL) 13, an organic light-emittinglayer (LEL) 14, and an organic electron-transporting layer (ETL) 15 areformed in sequence by a physical vapor deposition, as will be describedin more detail hereinafter. A plurality of laterally spaced secondelectrodes 16 (also referred to as cathodes) are formed over the organicelectron-transporting layer 15, and in a direction substantiallyperpendicular to the first electrodes 12. An encapsulation or cover 18seals environmentally sensitive portions of the device, therebyproviding a completed OLED 10.

Turning to FIG. 2, a schematic perspective view of an OLED apparatus 100is shown which is suitable for making a relatively large number oforganic light-emitting devices or displays using automated or roboticmeans (not shown) for transporting or transferring substrates among aplurality of stations extending from a buffer hub 102 and from atransfer hub 104. A vacuum pump 106 via a pumping port 107 providesreduced pressure within the hubs 102, 104, and within each of thestations extending from these hubs, except for station 140. A pressuregauge 108 indicates the reduced pressure within the apparatus 100. Thepressure is typically lower than 10⁻³ Torr (1.33×10⁻¹ Pascal) and can beas low as 10⁻⁶ Torr (1.33×10⁻⁴ Pascal).

The stations include a load station 110 for providing a load ofsubstrates, a vapor deposition station 130 dedicated to forming organichole-transporting layers (HTL) which may include organic hole-injectingsub-layers, a vapor deposition station 140 dedicated to forming organiclight-emitting layers (LEL), a vapor deposition station 150 dedicated toforming organic electron-transporting layers (ETL), a vapor depositionstation 160 dedicated to forming the plurality of second electrodes(cathodes), an unload station 103 for transferring substrates from thebuffer hub 102 to the transfer hub 104 which, in turn, provides astorage station 170, and an encapsulation station 180 connected to thehub 104 via a connector port 105. Each of these stations, except for LELstation 140, has an open port extending into the hubs 102 and 104,respectively, and each station has a vacuum-sealed access port (notshown) to provide access to a station for cleaning, and for replacementor repair of parts. Each station includes a housing, which defines achamber.

The inventive method of color pixelating organic layers in making anOLED display uses directed beams which are generated by inducing viscousflow of an inert gas through nozzles, the viscous gas flow transportingwith it vapors of organic materials. Depending on the number and insidedimensions of the nozzles, as well as the gas flow required to achievedirected beams, the “gas loading” of LEL station 140 can be relativelyhigh. Such relatively high “gas loading” could adversely affect thefunctioning of other stations of the OLED apparatus 100.

In order to prevent such potentially adverse effects on other stationsand hubs of the OLED apparatus 100, the LEL station 140 is adapted toisolate this station during color pixelation. Isolation is achieved by:(i) a station valve 141, shown in dashed outline proximate the bufferhub 102, is normally in a closed position. Station valve 141 is openedonly to permit transfer of a substrate from the buffer hub into station140, and again to transfer a completed substrate, i.e. a color pixelatedsubstrate, from station 140 into the buffer hub 102; and (ii) a stationvacuum pump 142 is connected to station 140 via a station pumping port144 which includes a throttle valve 145. The throttle valve can becontrolled to be in a fully open position, throttled to a partially openposition, or to be in a closed position. A station pressure sensor 146indicates the pressure within a chamber of station 140.

Prior to substrate transfer(s) the throttle valve 145 is adjusted sothat substantially identical pressure indications are obtained fromstation pressure sensor 146 and from pressure gauge 108 of the OLEDapparatus 100, and the station valve 141 can then be opened.

Upon transfer of a substrate from the hub 102 into the chamber (140C) ofstation 140, the station valve 141 is closed and the throttle valve 145is opened to provide for evacuation of the chamber (140C) to an initialpressure in a range from 10⁻⁷ to 10⁻⁵ Torr (1.33×10⁻⁵ to 1.33×10⁻³ Pa)in order to remove traces of oxygen and moisture from the chamber.

Prior to color pixelation, inert gas may optionally be admitted into thechamber (140C) from an inert gas supply 147 via a conduit 148 includinga gas flow controller 149. The throttle valve 145 is throttled to aposition so that the gas pressure (P_(c)) in the chamber equilibrates toa selected level in a range from about 10⁻⁷ to 10⁰ Torr. The gaspressure level in the chamber is lower than the pressure of an inertgas, which is used to cause viscous flow in the nozzles (506) to providethe directed beams.

FIG. 3 is a schematic section view of the load station 110, taken alongsection lines 3—3 of FIG. 2. The load station 110 has a housing 110H,which defines a chamber 110C. Within the chamber is positioned a carrier111 designed to carry a plurality of substrates 11 having preformedfirst electrodes 12 (see FIG. 1 and FIGS. 4–5). An alternative carrier111 can be provided for supporting a plurality of active matrixsubstrates 51 (see FIG. 7). Carriers 111 can also be provided in theunload station 103 and in the storage station 170.

Turning to FIG. 4, a schematic top view of a full-color (RGB) passivematrix OLED display 10-3C is shown which can be color pixelated by themethod of the present invention. Like numeral designations correspondlike parts or functions given in the description of FIG. 1. Each pixel(labeled pix in FIG. 4) comprises three adjacent subpixels, labeled R,G, and B. Each subpixel is formed at the intersection of a columnelectrode or anode 12 and a row electrode or cathode 16. Each subpixelcan be addressed independently to emit a specific color. For example, asubpixel labeled R has an organic EL medium, which emits red light.Likewise, the subpixels labeled G and B have organic EL media, whichemit green and blue light, respectively. Each pixel, therefore, hasthree independently addressable column electrodes 12 (anodes) and oneaddressable row electrode 16, and the OLED display 10-3C has three timesas many column electrodes or anodes 12 as row electrodes or cathodes 16.Note that a simple column stripe pattern is shown in FIG. 4, but morecomplicated pixel patterns such as the commonly used delta pattern, isalso possible.

FIG. 4 shows a limited number of pixels (pixes). In principle, thenumber of pixels is limited only by the size of the substrate 11 uponwhich the display 10-3C is fabricated. The pixel resolution, or thenumber density of pixels can be made quite high, limited only by theresolution of the patterning method to produce color pixelation. Usingthe directed beam deposition of the present invention can permit pixelresolution as high as 50 pixels per millimeter.

In one type of OLED display, commonly called a bottom emitting display,a selected pattern of light emission from the OLED display 10-3C isproduced which can be observed by viewing the bottom surface of thelight-transmissive substrate 11. In a preferred mode of operation, thepanel is stimulated to emit light by sequentially stimulating one row ofpixels at a time and repeating the stimulating sequence at a rate chosenso that the interval between repeated stimulation of each row is lessthan the detection limit of the human visual system, typically less thanabout 1/60^(th) of a second. An observer sees an image formed byemission from all stimulated rows, even though the panel at any instantin time is emitting light from addressed subpixels in only one row.

The RGB color pixelation of the OLED panel 10-3C is shown as a stripepattern in which each of the R, G, and B stripes produces light emissiononly from areas defined by the intersection of a column electrode(anode) 12 and a row electrode (cathode) 16 when stimulated, even thoughthe definition of a pixel pix includes the non-emitting gaps (notlabeled in FIG. 4) between the anodes 12.

FIG. 5 is a schematic sectional view of the OLED display, taken alongthe section lines 5—5 of FIG. 4. The EL medium includes an organichole-transporting layer 13 formed as a continuous layer over and betweenthe anode column electrodes 12 which are provided on the substrate 11.The hole-transporting layer can include a hole-injecting sublayer (notshown) formed first over and between the anodes. Organic light-emittingsubpixel layers 14R, 14G, and 14B are formed over the hole-transportinglayer. An organic electron-transporting layer 15 is formed as acontinuous layer over the color pixelated layers, and can include anoverlaying electron-injecting layer (not shown) in contact with thecathode row electrode(s) 16.

Turning to FIG. 6, a circuit diagram of a portion of an active matrixOLED display is depicted. Each one of repeating subpixel circuitsincludes a thin-film switching transistor TSnm where n, m are integerswhich define the specific location of the subpixel circuit formed on alight-transmissive substrate 51 (see FIG. 7). For example, TS12 is athin-film switching transistor associated with a subpixel circuitlocated in a row 1 and in a position 2 or a column 2 of that row. Eachsubpixel circuit further includes a thin-film transistor TCnm for powercontrol, a thin-film capacitor Cnm, and an organic EL medium ELnm whichare depicted as diodes. Power supply lines Vddn, X-direction signallines (including lines X1 to Xn, where n is an integer), and Y-directionsignal lines (including lines Y1 to Ym, where m is an integer) provideelectrical potentials and signal addressing capability, respectively, toeach subpixel circuit. Circuits in row 1, defined by signal addressinglines X1 and Y1–Y3, are indicated as 61-1, 61-2, and 61-3, respectively,and like numeral designations are used in FIG. 7. The X-directionsignals lines X1, X2, X3, . . . Xn are connected to an X-directiondriving circuit 87, and the Y-direction signals lines Y1, Y2, Y3, . . .Ym are connected to a Y-direction driving circuit 88. To provide lightemission, for example, from the EL medium EL 12, signals are provided atX-direction signal line X1 and at Y-direction signal line Y2, therebyactuating the thin-film switching transistor TS12 into an “on” state. Inturn, the thin-film transistor for power control TC12 comes into an “on”state and induces electric current flow through the EL medium EL12provided via the power supply line Vdd1. Thus, light is emitted by theOLED EL12. Why here

FIG. 7 is a schematic sectional view of the portion of subpixels 61-1,61-2, and 61-3 indicated in FIG. 6, and showing a full-color pixelatedEL medium in which RGB color pixelation of the light-emitting layer isdesignated at 54R, 54G, and 54B, respectively. Color pixelation can beachieved by the method of the invention.

On a light-transmissive substrate 51 are provided the subpixel circuitelements (thin-film transistors, thin-film capacitor, and electricalwiring) 61-1, 61-2, and 61-3. Conductive wiring 64 provides anelectrical connection (from a thin-film transistor for power control) toa light-transmissive first electrode or anode pad 52 which can beconstructed of indium-tin-oxide (ITO). A light-transmissive organicinsulator layer 66 provides electrical insulation. A second organicinsulator layer 68 encases edges and portions of upper surfaces of thepads 52.

The organic EL medium is then formed, comprised of, in sequence, acontinuous organic hole-injecting and hole-transporting layer 53, thecolor pixelated organic light-emitting layers 54R, 54G, and 54B, and acontinuous electron-transporting layer 55. A common second electrode orcathode 56 is formed in contact with the electron-transporting layer 55.Effective dimensions of light emission from subpixels are indicated byarrows extending between dashed lines, while a pixel pix includes notonly these light emission portions but also non-emissive raised portionswhich extend between the recessed light emission portions 54R, 54G, and54B.

Turning to FIG. 8, a schematic rendition of a vapor deposition apparatus500 is shown which is useful in practicing the present invention. Thestation 140 of FIG. 2 has a housing 140H which defines a chamber 140Cwhich is held at a reduced pressure P_(c) as described with reference toFIG. 2. In order to preserve clarity of the drawing, the station valve141, the station vacuum pump 142 and associated pumping port 144 andthrottle valve 145, the station pressure sensor 146, as well as theinert gas supply 147 with conduits 148 and gas flow controller 149, havebeen omitted in FIG. 8. Moreover, depending on the material in thesubstrate 11 (51), manifold-to-substrate spacing and depositiontemperatures, the substrate may have to be cooled and, for convenienceof illustration, a cooling structure has also not been shown.

Disposed in the chamber 140C is a manifold 500M which includes amanifold housing 502 which is sealingly covered on at least one surfaceby a structure which is also referred to as a nozzle plate 504. Thenozzle plate has a plurality of nozzles 506, which extend into themanifold. The structure or nozzle plate has alignment marks 533 formedon one surface which serve to align an OLED display substrate 11 (51)with respect to the nozzles prior to vapor depositing the first one of acolor pixelated organic light-emitting layer 14R, 14G, or 14B as astripe pattern on the substrate. It is understood that the substrate 11(51) includes an organic hole-injecting and hole-transporting layer(HTL) 13 or 53.

Upon aligning a substrate in the chamber 140C in a y-direction withrespect to the nozzles 506 via the alignment marks 533 and alignmentwindows 233 provided on a holder or mask frame 230 in which a substrateis positioned (see FIGS. 16 and 17), the substrate 11 (51) is moved inan x-direction to a starting position “I” by a lead screw 212 (see FIGS.16 and 17). It will be understood that either the substrate 11 (51) orthe manifold 500M can be moved. Of course, deposition can also beaccomplished if either of these elements is stationary.

A plurality of organic material vapor sources 500VS1 to 500VS4 is showndisposed outside of the chamber 140C. In order to coat a light-emittinglayer at least one of the materials in vapor sources 500VS1 to 500VS4would be a light-emitting material. Alternatively the said plurality ororganic material vapor sources 500VS1 to 500 VS4 could be disposedinside of the chamber 140C and/or inside of manifold 500M. Each vaporsource includes a housing 540. As depicted schematically in FIG. 8 anddescribed in greater detail with reference to FIG. 15, the housing 540includes a flange 541 which sealingly mates with a source cover 544 andwhich, in turn, is sealingly attached to a lower vapor transport conduit546 a. A vapor flow control device 560 v is connected at one terminationto the lower vapor transport conduit 546 a, and at a second terminationto an upper vapor transport conduit 546 b. Each vapor source 500VS1 to500VS4 also preferably includes an individual heating element not shownin FIG. 8 for heating the material inside to an appropriate temperatureto create a vapor of that organic material placed within the vaporsource. Alternatively the said organic material can be loaded directlyinto manifold 500M without the use of separate said vapor sources 500VS1to 500VS4, and organic vapor created through the use of a heatingelement (not pictured) placed directly on or in the manifold 500M.

An inert gas supply 500IGS has a gas shut-off valve 562 and a conduit(not identified in the drawing) leading from the gas shut-off valve intoan inert gas preheater 564 for heating the gas to a temperaturesufficient to prevent condensation of organic material vapors on innersurfaces of elements in which both the inert gas flow and flow of anorganic material vapor are present. A lower gas transport conduit 566 aconnects the inert gas preheater to one termination of a gas flowcontrol device 560 g, and an upper gas transport conduit 566 b connectsa second termination of the gas flow control device 560 g to a combiner570. The combiner 570 also accepts the upper vapor transport conduits546 b, and combines inert gas flow and at least a portion of organicmaterial vapor from two organic material vapor sources which areoperative concurrently, as will be described further hereinafter. Acommon conduit 546 c for vapor transport and gas transport connects anoutput termination of the combiner 570 to the manifold 500M through thehousing 140H of the vapor deposition station 140. Alternatively, inertgas could be fed directly into the manifold 500M and mixed with organicvapor that has been transported or generated there.

The organic material vapor sources, the inert gas preheater, the flowcontrol devices, the combiner, and the transport conduits are arrangedwithin a heatable enclosure 600 shown in dashed outline. The heatableenclosure can be an appropriately sized and configured laboratory ovenwhich can be controllably heated to provide a temperature T_(e) withinthe enclosure sufficient to prevent condensation of organic materialvapors on inside surfaces of the vapor sources, conduits, vapor flowcontrol devices, and the combiner 570.

Likewise, to prevent condensation of organic material vapors on innersurfaces of the manifold 500M and the surface of the structure or nozzleplate 504 facing the manifold, and to prevent clogging of the nozzles506 by vapor condensation, the manifold can be heated by manifoldheating lamps 520. Not shown in FIG. 8 is a controllable heating lamppower supply and electrical connections to the heating lamps 520. Itwill be appreciated that, for example, heating coils or heating stripscan be used equally effectively in heating the manifold and the nozzleplate.

It has been found unexpectedly that highly directed beams of gas with avery small angular divergence from the nozzle axis will exit from thenozzles 506 if gas flow is controlled by the gas flow control device 560g such that a resulting gas pressure in the manifold 500M causes viscousflow of the gas from the manifold through the nozzles and into thechamber 140C. It has also been found that organic material vapors can becombined with flowing inert gas in the combiner 570 to be transportedinto the manifold 500M, and to issue from the nozzles 506 as combineddirected beams 510 of organic material vapors and inert gas. It has alsobeen established for directed gas beams, that collimation can beretained over a distance in a range from about 0.02 to 2.0 centimeterabove the structure or nozzle plate 504 depending on an insidedimensions of the nozzles and on a level of gas flow into the manifoldwith corresponding increase of gas pressure therein.

Alternatively it has also been found that that highly directed beams ofgas with a very small angular divergence from the nozzle axis will exitfrom the nozzles 506 if gas flow is controlled by the gas flow controldevice 560 g such that a resulting gas pressure in the manifold 500Mcauses viscous flow of the gas from the manifold through the nozzles andinto the chamber 140C when the said organic material is vaporizeddirectly in said manifold 500M.

Alternatively it has also been found that that highly directed beams ofgas with a very small angular divergence from the nozzle axis will exitfrom the nozzles 506 if gas flow is controlled by the gas flow controldevice 560 g such that a resulting gas pressure in the manifold 500Mcauses viscous flow of the gas from the manifold through the nozzles andinto the chamber 140C when the said organic material is vaporizeddirectly in said manifold 500M and is combined with an inert gas inmanifold 500M.

In an effort to provide improved understanding of forming a directedbeam of a gas flowing though a nozzle under conditions of viscous flow,pertinent sections of “Handbook of Thin Film Technology”, edited by LeonI. Maissel and Reinhard Glang, published by McGraw Hill Book Company in1970 and “Foundations of Vacuum Science and Technology edited by JamesM. Lafferty, published by John Wiley & Sons, Inc. are referenced.

If a gas is flowing through a narrow tube it encounters resistance atthe walls of the tube. Thus, gas layers at and adjacent to the walls areslowed down, causing viscous flow. A viscosity coefficient η resultsfrom internal friction caused by intermolecular collisions. Thisviscosity coefficient η is given by

$\begin{matrix}{\eta = {\frac{2f}{\pi\;\sigma^{2}}\left( \frac{{mk}_{B}T}{\pi} \right)^{\frac{1}{2}}}} & (1)\end{matrix}$where f is a factor between 0.3 and 0.5 depending on the assumed modelof molecular interaction. For most gases, f=0.499 is a good assumption.σ is the molecular diameter; m is the mass of a gas molecule; κ_(B) isthe Boltzmann constant; and T is the temperature of the gas, given inKelvin (K).

Specifically, for a straight cylindrical tube of length l and a radius rhaving an inert gas flowing through it a viscous flow microscopic flowrate Q_(visc) can be given by

$\begin{matrix}{Q_{visc} = {\frac{\pi\; r^{4}}{8\;\eta\; 1}{\overset{\_}{p}\left( {p_{2} - p_{1}} \right)}}} & (2)\end{matrix}$wherein {overscore (p)} is the average pressure in the tube, and p₂ andp₁ are the pressures at opposing ends of the tube.

The mean free path of a gas λ is given by

$\begin{matrix}{\lambda = {\frac{k_{B}T}{\sqrt{2}{\pi\sigma}^{2}P} = \frac{1}{\sqrt{2}\pi\; n\;\sigma^{2}}}} & (3)\end{matrix}$where σ is the molecular diameter, n is the number of molecules per unitvolume and P is the gas pressure.

When gas flows through a tube of diameter d there are in general threeflow regimes being free molecular flow, continuum or viscous flow andtransitional flow that can be used to characterize the flow. Knudsen'snumber Kn given byKn=λ/d  (4)is used to characterize the flow regime. When Kn>0.5 the flow is in thefree molecular flow regime. Here gas dynamics are dominated by molecularcollisions with the wall of the tube or vessel. Gas molecules flowthrough the tube by successive collisions with the walls untilexperiencing a final collision, which ejects them through the opening.Depending on the length to diameter ratio of the tube the angulardistribution of emitted molecules can range from a cosine thetadistribution (for zero length) to a heavily beamed profile (for largelength to diameter ratio) (see Lafferty for details). Even in the caseof the heavily beamed profile, there is a significant component of theemitted flux at non zero angles to the axis of the tube. When0.01<Kn<0.5 the flow is in the transitional flow regime in which bothmolecular collisions with the wall and intermolecular collisionsinfluence flow characteristics of the gas. As Kn gets lower we approachthe viscous flow regime and the flow is dominated by intermolecularcollisions. When Kn<0.01 the flow is in the viscous flow regime. Herethe mean free path of the gas is small compared to the diameter of thetube and intermolecular collisions are much more frequent than wallcollisions. When operating in the viscous flow regime gas coming out ofthe tube orifice usually flows smoothly in streamlines generallyparallel to the walls of the orifice and can be highly directed in thecase of large length to diameter ratios.

For certain vaporizable materials, the vapor pressure at usefultemperatures is low enough that it is difficult to attain viscous flowfor small openings, such as would be useful in producing pixilated OLEDdisplays. In such cases, an additional gas (for example an inert gasacting solely as a carrier) may be used to produce the viscous flow.

The vapor pressure p* of a gas can be approximated from the relationshipLog p*=A/T+B+C Log T  (5)where A, B, and C are constants. The vapor pressure of Alq has beenmeasured to vary from 0.024–0.573 Torr from 250–350° C. The best fitcoefficients were found to be A=−2245.996, B=−21.714 and C=8.973. Themean free path for Alq varies from 0.5–0.0254 mm at the vapor pressureover the temperature range 250–350° C. Thus the vapor pressure of Alqalone is insufficient to produce viscous flow in a circular nozzlestructure with a 100 μm tube diameter over the temperature range250–350° C. A vapor pressure of approximately 15 Torr will be requiredto get into the viscous flow regime for Alq and this tube diameter.

The vapor flow control devices 560 v and the gas flow control device 560g can be manually adjustable flow control valves. Alternatively, theseflow control devices can be mass-flow control devices which can beadjusted in a graduated manner from a closed position to an openposition in response to electrical control signals provided bycontrollers which, in turn, can be addressed by signals from a computer(not shown).

One of the organic material vapor sources, for example the vapor source500VS4, is charged with a vaporizable organic host material. Thisorganic host material can be in the form of a powder, flakes,particulates or liquid. If a full-color (RGB) OLED display is to beformed, each of the remaining organic material vapor sources, forexample the vapor sources 500VS1, 500VS2, and 500VS3, is charged with adifferent vaporizable organic dopant material. For example, the vaporsource 500VS1 is charged with a dopant material, which provides greenlight emission from a pixelated doped layer 14G of the organic hostmaterial. The vapor source 500VS2 can be charged with a dopant material,which provides red light emission from a pixelated doped layer 14R ofthe organic host material. The vapor source 500VS3 receives a dopantmaterial, which provides blue light emission from a pixelated dopedlayer 14B of the organic host material. The organic dopant materials canbe in the form of a powder, flakes, particulates or liquid.

Using the above described examples of the vapor sources and therespective charges of organic materials, the vapor deposition apparatus500 can be operated as follows to provide full-color pixelation on asubstrate 11 or on a substrate 51, depicted here as a stripe pattern ofa light-emitting layer 14R (or 14G, or 14B). The vapor source 500VS2(red dopant) and the vapor source VS4 (host material) are heated tovaporization temperatures which causes the respective organic materialsto vaporize, usually by sublimation. The corresponding vapor flowcontrol devices 560 v are actuated so that a controlled dopant vaporflow and a controlled host vapor flow passes from these two vaporsources via lower and upper vapor transport conduits (546 a and 546 b,respectively), the combiner 570, and the common conduit 546 c, into themanifold 500M in which complete “molecular mixing” of the host materialvapor and the dopant material vapor are achieved. These vapors of theorganic materials create a vapor pressure PV within the manifold whichcan be approximately 0.024–0.573 Torr over the sublimation range from250–350° C. for Alq, as described in more detail in conjunction withFIG. 14.

Flow of an inert gas, for example nitrogen or argon gas, is initiated bycontrolling an opening in the gas flow control device 560 g upon openingthe gas shut-off valve 562 which is included in the inert gas supply500IGS. The flowing inert gas is preheated in the inert gas preheater564, and preheated gas passes into the manifold 500M via lower and uppergas transport conduits (566 a and 566 b, respectively), the combiner570, and through the common conduit 546 c for vapor transport and gastransport. The inert gas provides a gas pressure P_(G) in the manifoldwhich is adjusted (via gas flow control device 500 g) to be sufficientto cause viscous flow of the gas through the nozzles 506 in thestructure or nozzle plate 504, and to provide substantially directedbeams of inert gas which transport with them the mixed vapors of theorganic materials introduced into the manifold to achieve the directedbeams 510 of organic material vapors and inert gas.

The OLED display substrate 11 (51) had been previously oriented withrespect to the nozzles 506 by aligning it in a y-direction via thealignment marks 533 on the nozzle plate and corresponding alignmentwindows 233 disposed on a holder or mask frame 230 for holding thesubstrate (not shown in FIG. 8, see FIGS. 16, 17). The substrate ismoved in an x-direction over and past the directed beams 510 to receivein designated subpixels in a stripe pattern an organic redlight-emitting layer 14R. The stripe pattern is provided by moving ortranslating the substrate in a forward motion “F” from a startingposition “I” to an end position “II” of forward motion. Alternatively,it is possible to fix the substrate position and translate the manifoldin reference to that substrate.

Vapor flow from the vapor sources 500VS4 (host material) and 500VS2 (reddopant) is now discontinued by closing the corresponding vapor flowcontrol devices 560 v, and by discontinuing heating of the vapor source500VS2. The flow of preheated gas into the manifold and through thenozzles can continue, or it can be discontinued by closing the gas flowcontrol device 560 g. Additionally, a shutter device (see FIG. 16) canbe positioned over the nozzle plate to block residual vapor streams orresidual directed beams from reaching the substrate during a reverse orreturn motion “R” from the position “II” to the position “I”.

The substrate 11 (51) is now moved or translated from the position “II”by a reverse or return motion “R” back to the starting position “I”. Thevapor source 500VS1 (green dopant) is heated to cause sublimation ofthis dopant and introduction of “green” dopant vapors into the manifoldat a vapor flow controlled by the vapor flow control device 560 vassociated with the vapor source 500VS1. The steps of providing vapor ofthe host material from source 500VS4 into the manifold, and to createdirected beams 510 by flowing the preheated inert gas into the manifold500M to cause viscous flow in the nozzles 506, are repeated. In position“I”, the substrate is reoriented or indexed with respect to the nozzlesso that subpixels designated to receive an organic green light-emittinglayer 14G are aligned with the nozzles. The substrate is then moved ortranslated in a forward direction “F” over and past the directed beamsissuing from the nozzles 506 to the position “II” to receive in a stripepattern in the designated subpixels an organic green light-emittinglayer 14G.

The above described process steps are repeated by forming a stripepattern of an organic blue light-emitting layer 14B in designatedsubpixel locations of the substrate 11 (51) via the vapor sources 500VS3(blue dopant) and 500VS4 (host material). Thus, if desired, a full-colorRGB color pixelated OLED display 10-3C or 50-3C can be achieved by themethod of the invention in a vapor deposition apparatus 500.

It will be appreciated that a multicolor OLED display can be madeequally effectively by the inventive method. A structure or nozzle plate504 having nozzles 506 arranged to correspond to selected columns (orrows) of subpixels is used for that purpose.

FIG. 8 and its description include four vapor sources 500VS1 to 500VS4.It will be understood that more or fewer vapor sources can be used inpracticing color pixelation by the inventive method. Also, the selectionof vaporizable organic materials charged into vapor sources can bedifferent from the materials described with reference to FIG. 8. Forexample, a first vapor source can be charged with a first vaporizableorganic host material, and a second vapor source can receive a secondvaporizable organic host material. A third vapor source, or a third andadditional vapor sources, can be charged with vaporizable organic dopantmaterials which are selected to cause emission of one of red, green, orblue light from a pattern of a doped organic light-emitting layer of anoperative OLED display.

Using two organic host materials and one or more organic dopantmaterials in forming the doped organic light-emitting layer can provideimproved operational stability, or improved light emission, or improvedcolor of emitted light, or combinations of such improved features, of anoperative OLED display.

One or more vaporizable organic dopant materials can be charged into onevapor source.

Upon completion of color pixelation, all vapor sources are deactuated bydiscontinuing the heating of the sources, and the inert gas flow isdiscontinued by closing the gas shut-off valve 562 or by controlling theclosing of the gas flow control device 560 g. The completed substrate ismoved or translated in an x-direction from the position “II” back to theposition “I”. The substrate 11 (51) can be removed from the chamber 140Cin this latter position via the station valve 141 shown in FIG. 2 oncethe inert gas flow into the chamber has been discontinued and thechamber 140C has been evacuated (by station vacuum pump 142 via throttlevalve 145) to a pressure which is approximately equal to the pressureprevailing in the buffer hub 102 of FIG. 2. The color pixelatedsubstrate can then be advanced into the station 150 (ETL) for vapordeposition of an organic electron-transporting layer, which can includean electron-injecting sublayer.

Turning to FIG. 9, a structure or nozzle plate 504 is shown having aplurality of nozzles 506 arranged along a center line CL. The nozzlepitch, which is the equal spacing s between nozzles, is selected toproduce the necessary deposition pattern that accurately coats thedesired subpixels of an OLED display. The total number of nozzles 506corresponds to a total number of subpixels of an OLED display which aredesignated to emit light of a selected color such as, for example redlight, green light, or blue light. Alignment marks 533 are shown here inthe form of alignment crosses, but other alignment methods can beutilized.

FIG. 10 is a sectional view of the nozzle plate 504, taken along thesection lines 10—10 of FIG. 9. A nozzle inside dimension or a nozzlediameter d and a nozzle length dimension 1 are indicated. Nozzles 506can be of a circular outline or of a polygonal outline. Nozzle insidedimensions d can be in a range from 10 to 1000 micrometer, and directedbeams 510 (see FIG. 8) of organic material vapors and inert gas can beachieved providing that the nozzle length dimension l is at least 5times larger than the nozzle inside dimension d.

Turning to FIG. 11, a structure or nozzle plate 504T is shown whichincludes a two-dimensional array of nozzles 506 as well as alignmentmarks 533. The nozzle array 504T is depicted with m columns of nozzlesand having n rows of nozzles. Such nozzle plate 504T can be sealinglypositioned on one side of an appropriately sized manifold, and a shutterdevice can be positioned between the nozzle array 504T and an OLEDdisplay substrate which is to receive color pixelation so that theshutter device blocks direct line-of-sight between the nozzles 506 andthe substrate. The substrate is oriented with respect to the nozzles viathe alignment marks 533 and corresponding alignment windows 233 (seeFIGS. 16, 17) formed on a holder or mask frame 230 which accepts andtransports the substrate. The substrate is moved to be positioned overthe nozzle plate 504T and in alignment therewith. The shutter device isthen withdrawn, and directed beams of inert gas and vapors of an organichost material and of a color-forming dopant material are forming a dopedorganic light-emitting layer (such as a layer 14R, or 14G, or 14B) ondiscrete and selected subpixels of the substrate, as distinguished overthe continuous motion or translation of a substrate over and pastdirected beams to produce a stripe pattern of color pixelation.

Turning to FIG. 12, a schematic top view of a cylindrical tubularmanifold 500CM is shown. The manifold 500CM has a cylindrical manifoldhousing 536, which includes end caps 538 and 539. Manifold heatingelements 520 extend throughout the manifold and are supported by the endcaps. A plurality of nozzles 506 is formed directly in the housing 536as a line pattern along a center line CL. Alignment marks 535 areprovided along the cylindrical surface and positioned along the centerline CL.

FIG. 13 is a sectional view of the cylindrical manifold, taken along thesection lines 13—13 of FIG. 12, and defining a nozzle length dimension 1and a nozzle inside dimension d. The nozzle inside dimension d can be ina range from 10 to 1000 micrometer, and the nozzle length should be atleast 5 times larger than the nozzle diameter. Other configurations oftubular manifolds can be used such as, for example, tubular manifoldshaving an ellipsoidal cross-section or a polygonal cross-section.

FIG. 13A shows a sectional view of a modified cylindrical tubularmanifold 500CM-1 in which a curved structure or curved nozzle plate 504Cis sealingly disposed over a slit-shaped aperture 537 formed in thecylindrical manifold housing 536. Nozzles 506 are formed in the curvednozzle plate 504C along a line such as shown for the line of nozzles inFIG. 12. Alignment marks 535 are provided on the curved nozzle plate(not shown in FIG. 13A).

Turning to FIG. 14, a relationship is indicated schematically betweendivergence of an organic material vapor stream issuing from a nozzle 506and, respectively, a vapor pressure P_(V) within the manifold housing502 and the vapor pressure P_(V) plus inert gas pressure levels P_(G1)and P_(G2) in the manifold 500M. The divergence is indicated by dashedarrows and angles α₁, α₂, and α₃ subtending the streams issuing from thenozzle 506 formed in the nozzle plate 504. The reduced pressure P_(c) inthe chamber 140C, which can include a pressure of an inert gas admittedinto the chamber (see FIG. 2), can be in a range from 10⁻⁷ to 10⁰ Torr.

When, in the absence of inert gas flow into the manifold 500M, vapors oforganic host materials and of a dopant are introduced into the manifoldfrom respective vapor sources, a vapor pressure P_(v) of approximately0.1 Torr (13 Pa) is formed in the manifold at a sublimation temperatureof about 300° C. in the organic material vapor sources. Such organicmaterial vapors at this vapor pressure provide a non-viscous flowthrough the nozzle 506 and enter the chamber with relatively highdivergence as shown by the subtended angle α₁. When inert gas flow isadditionally introduced into the manifold so as to cause a gas pressureP_(G1), the divergence of the vapor stream plus the inert gas streamissuing from the nozzle is reduced as depicted by the subtended angleα₂, indicating that the introduction of the inert gas has caused somelevel of viscous flow behavior. When inert gas flow into the manifold500M is further increased to cause a gas pressure P_(G2)>P_(G1) in themanifold, the divergence of the vapor stream and of the inert gas streamissuing from the nozzle 506 is further reduced to provide asubstantially directed beam having a subtended angle α₃, indicating asubstantial contribution to viscous flow through the nozzle 506 by theinert gas at the latter gas pressure level in the manifold 500M.

Turning to FIG. 15, a sectional view of an embodiment of a vapor source500VS is shown which is representative of the vapor sources500VS1–500VS4 depicted schematically in FIG. 8. The vapor source 500VSincludes a housing 540 having a flange 541. A gasket 542 provides asealing engagement between the flange 541 and a source cover 544 viabolts 543 which are provided around the periphery of the flange and ofthe source cover. The gasket 542 can be an annular compression gasketmade of a metal such as aluminum or copper, as is well known to thoseskilled in the art of vacuum technology.

A vaporization heater 550 extends within the housing 540, supported byfeedthroughs 552 and 554, which are provided in the source cover 544.The vaporization heater 550 can be heated to a vaporization temperaturewhich causes a vaporizable organic material 14 a (shown in dashedoutline) received in the vapor source 500VS to sublime and to providevapors (not shown) into the lower vapor transport conduit 546 a (seealso FIG. 8). This conduit is sealed against the source cover 544 by aseal 545.

A vaporization heater power supply 750 is connected via a lead 752 tothe feedthrough 552 and via a lead 754 to the feedthrough 554.Controlled heating of the vaporization heater 550 is achieved bycontrolling or regulating electrical current flow through the heater 550with a regulator 750R. Current flow is indicated by a current meter 753.

The housing 540 of the vapor source 500VS can be detached from thesource cover 544 by removing the bolts 543. Detaching the housingpermits cleaning of residue of organic material 14 a, and allows forcharging a fresh supply of organic material 14 a.

This embodiment of a detachable vapor source and other embodiments ofdetachable vapor sources useful in the practice of the present inventionhave been disclosed in a commonly assigned U.S. patent application Ser.No. 10/131,926, filed on Apr. 25, 2002, now U.S. Pat. No. 6,749,906 andentitled “Thermal Physical Vapor Deposition Apparatus With DetachableVapor Source(s)”, by Steven A. Van Slyke, the disclosure of which isherein incorporated by reference.

Turning to FIG. 16, a schematic sectional view of the vapor depositionstation 140 (LEL) of FIG. 2 is shown, taken along the section lines16—16 of FIG. 2. The vapor sources 500VS and the inert gas preheater 564have been omitted in this drawing. The common conduit 546 c extends intothe manifold 500M through a thermally insulative manifold support 530which is sealed with respect to the housing 140H by a gasket 532. Ashutter 238 can be moved into a position of covering the nozzles 506,shown in dashed outline, or into a position in which directed beams 510(not shown) can provide color pixelation of an OLED display substrate 11(51).

An OLED display substrate 11 (51) is positioned in a holder or maskframe 230 and has a spacing D from an upper surface of the nozzle plate504 and thus from the nozzles 506. A glide shoe 225 is fixedly attachedto an upper surface of the holder 230, and is depicted here as adovetail glide shoe. The glide shoe 225 glides matingly in a glide rail225R, which is formed in a lead screw follower 214.

The glide shoe and the glide rail permit motion of the holder 230 and ofa substrate 11 (51) retained therein in a y-direction (see FIG. 17) toprovide alignment of the substrate with respect to the nozzles, and toindex a substrate prior to each one of the color pixelating stepsdescribed with reference to FIG. 8.

A lead screw 212 engages the lead screw follower 214 and moves it (andthe holder 230) in an x-direction of a forward motion “F” from astarting position “I” to an end position “II” (shown in dashed anddotted outline). During this continuous motion, the substrate 11 (51)passes over and past directed beams (not shown) of organic materialvapors and of the inert gas to provide in a stripe pattern a pixelatedorganic layer.

The lead screw 212 is formed on portions of a lead screw shaft 211 whichis supported in at least two locations, namely in a shaft seal 211 aformed in the housing 140H of the station 140, and in a lead screw shafttermination bracket 213 which is mounted onto the housing 140H.

A lead screw drive motor 210 provides for forward motion “F” or forreverse or return motion “R” via switch 216 which provides a controlsignal to the motor from an input terminal 218 via a lead 217. Theswitch 216 can have an intermediate or “neutral” position (not shown inFIG. 16; see FIG. 17) in which the holder or mask frame 230 (and thesubstrate) can remain either in the end position “II” of forward motion,or in the starting position “I” in which a substrate 11 (51), havingreceived color pixelation during a previous pass over the nozzles, isremoved from the holder 230 and a new substrate is received in theholder or mask frame.

An alignment detector 234 serves to align the substrate 11 (51) withrespect to the nozzles 506 in the nozzle plate 504 via alignment marks533 (or via alignment marks 535 if a cylindrical manifold 500CM is used)which are aligned with alignment windows 233 formed in alignment tabs232 that can be attached to the holder or mask frame 230. The alignmentdetector detects alignment via an optical window 235 provided in thehousing 140H, and along an optical alignment axis 236. It is sufficientto provide optical alignment at either one of the alignment marks 533.

Turning to FIG. 17, a schematic top view of a portion of the LEL vapordeposition station 140 of FIG. 2 is shown. The manifold 500M ispositioned on the thermally insulative manifold support 530. Alignmenttabs 232 are shown attached to the holder or mask frame 230, andalignment windows 233 are formed in these tabs in the form of a cross tocorrespond with the cross-shaped alignment marks 533 provided on thenozzle plate 504 or to the cross-shaped alignment marks 535 on thecylindrical manifold 500CM of FIG. 12.

A stepper motor 220 has a drive shaft 222 which extends through thestepper motor and enters the chamber 140C through a shaft seal 223formed in the housing 140H. A shaft coupling 224 can be disengaged priorto motion or translation of the holder 230 in the x-direction via thelead screw 212 which engages the lead screw follower 214. The shaftcoupling 224 is disengaged by lifting the coupling lifter 226 which isattached to the portion of the drive shaft extending through the steppermotor 220. The stepper motor 220 provides precise indexing of thesubstrate 11 (51) in a y-direction under control of a computer 221 byproviding incremental rotation of the drive shaft 222 to advance or toretreat the holder 230 via the gliding mechanism provided by the gliderail 225R (see FIG. 16) and the glide shoe 225 when the shaft coupling224 is in the engaged position, as indicated in FIG. 17.

Turning to FIG. 18, a manifold assembly 500MA is shown schematicallypositioned in the chamber 140C. This manifold assembly is particularlyuseful in concurrently depositing in a three-color pattern organiclayers onto an OLED display substrate. The manifold assembly 500MAincludes three mechanically connected manifolds 500MB (for providingvapors of an organic host material and of a blue light-emitting dopant),500MG (for providing vapors of the organic host material and of a greenlight-emitting dopant), and 500MR (for providing vapors of the organichost material and of a red light-emitting dopant). Corresponding nozzles506B, 506G, and 506R, respectively, are offset among the three manifoldsof the assembly 500MA in correspondence to the spacing needed toaccurately coat the desired individual subpixels on an OLED displaysubstrate 11 (51). Only one of the manifolds is provided with one or twoalignment marks 533. It is noted that other alignment methods can alsobe utilized.

Each of the manifolds 500MB, 500MG, and 500MR receives a vapor of anorganic host material from, for example, the vapor source 500VS4 via avapor flow control device and via a common conduit 547 c for vaportransport from the host material vapor source and for transport of inertgas. The combiner 570 combines the organic host material vapor and thepreheated inert gas and delivers such combination into the commonconduit 547 c.

The manifold 500 MB also receives a “blue” dopant vapor provided in thisdrawing by the vapor source 500VS3. The manifold 500MG also receives a“green” dopant layer which is provided here by the vapor source 500VS1,and the manifold 500MR also receives a “red” dopant vapor provided bythe vapor source 500VS2.

As described above, the substrate 11 (51) is first oriented or alignedwith respect to, for example, the alignment marks 533 associated withmanifold 500MG. The substrate is then moved or translated along thex-direction to the starting position “I”. Directed beams are nextprovided through the nozzles 506B, 506G, and 506R. The substrate is thenmoved or translated over and past the directed beams to the end position“II” to receive concurrently a pattern of color pixelation in the formof repeating red, green, and blue stripes of light-emitting layers 14R,14G, and 14B, respectively, and in correspondence with designatedsubpixel columns to be formed on the OLED display substrate 11 (51). Itis understood that while a simple row/column pixelation structure isshown, the described invention can be coupled with shuttering, othermanifold geometries or other relative motion patterns to produce morecomplicated multicolor pixel deposition patterns.

Preferred materials for constructing the structure or nozzle plate(s)504, 504C, and 504T include metals, glass, quartz, graphite andceramics. The manifold housing 502, 536 can also be constructed from oneof the above preferred materials. The material for constructing themanifold housing need not be the same materials for constructing anozzle plate. For example, a manifold housing can be made of a metal,and nozzle plate can be made of glass.

It is understood that while PVD only has been discussed in thisdisclosure, the invention may also be used such that precursor speciesare fed into the manifold, reacted to form new molecular products, andthese new products issued in the described manner from the nozzle arrayand deposited on suitable substrates.

Other Features of an OLED Display

Substrate

The OLED display is typically provided over a supporting substrate whereeither cathodes or anodes of the OLED display can be in contact with thesubstrate. The electrodes in contact with the substrate are convenientlyreferred to as bottom electrodes. Conventionally, bottom electrodes arethe anodes, but this invention is not limited to that configuration. Thesubstrate can either be light-transmissive or opaque, depending on theintended direction of light emission. The light-transmissive property isdesirable for viewing the light emission through the substrate.Transparent glass or plastic is commonly employed in such cases. Forapplications where the light emission is viewed through the topelectrode(s), the transmissive characteristic of the bottom support isimmaterial, and therefore can be light-transmissive, light-absorbing orlight-reflective. Substrates for use in this case include, but are notlimited to, glass, plastic, semiconductor materials, silicon, ceramics,and circuit board materials. Of course it is necessary to provide inthese device configurations a light-transmissive top electrode or topelectrodes.

Anodes

When light emission is viewed through anodes 12 or anode pads 52, suchelectrodes should be transparent or substantially transparent to theemission of interest. Common transparent anode materials used in thisinvention are indium-tin oxide (ITO) and tin oxide, but other metaloxides can work including, but not limited to, aluminum- or indium-dopedzinc oxide (IZO), magnesium-indium oxide, and nickel-tungsten oxide. Inaddition to these oxides, metal nitrides, such as gallium nitride, andmetal selenides, such as zinc selenide, and metal sulfides, such as zincsulfide, can be used as anodes 12 (52). For applications where lightemission is viewed only through the cathode electrode or electrodes, thetransmissive characteristics of anodes are immaterial and any conductivematerial can be used, transparent, opaque or reflective. Exampleconductors for this application include, but are not limited to, gold,iridium, molybdenum, palladium, and platinum. Typical anode materials,transmissive or otherwise, have a work function of 4.1 eV or greater.Desired anode materials are commonly deposited by any suitable meanssuch as evaporation, sputtering, chemical vapor deposition, orelectrochemical means. Anodes can be patterned using well-knownphotolithographic processes.

Hole-Injecting Layer (HIL)

While not always necessary, it is often useful that a hole-injectinglayer be provided between anodes and a hole-transporting layer 13 (53).The hole-injecting material can serve to improve the film formationproperty of subsequent organic layers and to facilitate injection ofholes into the hole-transporting layer. Suitable materials for use inthe hole-injecting layer include, but are not limited to, porphyriniccompounds as described in U.S. Pat. No. 4,720,432, and plasma-depositedfluorocarbon polymers as described in U.S. Pat. No. 6,208,075.Alternative hole-injecting materials reportedly useful in organic ELdevices are described in EP 0 891 121 A1 and EP 1 029 909 A1.

Hole-Transporting Layer (HTL)

The hole-transporting layer 13 (53) of the organic EL display containsat least one hole-transporting compound such as an aromatic tertiaryamine, where the latter is understood to be a compound containing atleast one trivalent nitrogen atom that is bonded only to carbon atoms,at least one of which is a member of an aromatic ring. In one form thearomatic tertiary amine can be an arylamine, such as a monoarylamine,diarylamine, triarylamine, or a polymeric arylamine. Exemplary monomerictriarylamines are illustrated by Klupfel et al. U.S. Pat. No. 3,180,730.Other suitable triarylamines substituted with one or more vinyl radicalsand/or comprising at least one active hydrogen containing group aredisclosed by Brantley et al U.S. Pat. Nos. 3,567,450 and 3,658,520.

A more preferred class of aromatic tertiary amines are those whichinclude at least two aromatic tertiary amine moieties as described inU.S. Pat. Nos. 4,720,432 and 5,061,569. Such compounds include thoserepresented by structural formula (A)

wherein Q₁ and Q₂ are independently selected aromatic tertiary aminemoieties and G is a linking group such as an arylene, cycloalkylene, oralkylene group of a carbon to carbon bond. In one embodiment, at leastone of Q₁ or Q₂ contains a polycyclic fused ring structure, e.g., anaphthalene. When G is an aryl group, it is conveniently a phenylene,biphenylene, or naphthalene moiety.

A useful class of triarylamines satisfying structural formula (A) andcontaining two triarylamine moieties is represented by structuralformula (B)

where:

R₁ and R₂ each independently represents a hydrogen atom, an aryl group,or an alkyl group or R₁ and R₂ together represent the atoms completing acycloalkyl group; and

R₃ and R₄ each independently represents an aryl group, which is in turnsubstituted with a diaryl substituted amino group, as indicated bystructural formula (C)

wherein R₅ and R₆ are independently selected aryl groups. In oneembodiment, at least one of R₅ or R₆ contains a polycyclic fused ringstructure, e.g., a naphthalene.

Another class of aromatic tertiary amines are the tetraaryldiamines.Desirable tetraaryldiamines include two diarylamino groups, such asindicated by formula (C), linked through an arylene group. Usefultetraaryldiamines include those represented by formula (D)

wherein:

each Are may be an independently selected arylene group, such as aphenylene or anthracene moiety;

n is an integer of from 1 to 4; and

Ar, R₇, R₈, and R₉ are independently selected aryl groups. In a typicalembodiment, at least one of Ar, R₇, R₈, and R₉ is a polycyclic fusedring structure, e.g., a naphthalene.

The various alkyl, alkylene, aryl, and arylene moieties of the foregoingstructural formulae (A), (B), (C), (D), can each in turn be substituted.Typical substituents include alkyl groups, alkenyl, alkoxy groups, arylgroups, aryloxy groups, and halogen such as fluoride, chloride, andbromide. The various alkyl and alkylene moieties typically contain fromabout 1 to 6 carbon atoms. The cycloalkyl moieties can contain from 3 toabout 10 carbon atoms, but typically contain five, six, or seven ringcarbon atoms—e.g., cyclopentyl, cyclohexyl, and cycloheptyl ringstructures. The aryl and arylene moieties are usually phenyl andphenylene moieties.

The hole-transporting layer can be formed of a single or a mixture ofaromatic tertiary amine compounds. Specifically, one can employ atriarylamine, such as a triarylamine satisfying the formula (B), incombination with a tetraaryldiamine, such as indicated by formula (D).When a triarylamine is employed in combination with a tetraaryldiamine,the latter is positioned as a layer interposed between the triarylamineand the electron injecting and transporting layer. Illustrative ofuseful aromatic tertiary amines are the following:

-   1,1-Bis(4-di-p-tolylaminophenyl)cyclohexane-   1,1-Bis(4-di-p-tolylaminophenyl)-4-phenylcyclohexane-   4,4′-Bis(diphenylamino)quadriphenyl-   Bis(4-dimethylamino-2-methylphenyl)-phenylmethane-   N,N,N-Tri(p-tolyl)amine-   4-(di-p-tolylamino)-4′-[4(di-p-tolylamino)-styryl]stilbene-   N,N,N′,N′-Tetra-p-tolyl-4-4′-diaminobiphenyl-   N,N,N′,N′-Tetraphenyl-4,4′-diaminobiphenyl-   N,N,N′,N′-tetra-1-naphthyl-4,4′-diaminobiphenyl-   N,N,N′,N′-tetra-2-naphthyl-4,4′-diaminobiphenyl-   N-Phenylcarbazole-   4,4′-Bis[N-(1-naphthyl)-N-phenylamino]biphenyl-   4,4′-Bis[N-(1-naphthyl)-N-(2-naphthyl)amino]biphenyl-   4,4″-Bis[N-(1-naphthyl)-N-phenylamino]p-terphenyl-   4,4′-Bis[N-(2-naphthyl)-N-phenylamino]biphenyl-   4,4′-Bis[N-(3-acenaphthenyl)-N-phenylamino]biphenyl-   1,5-Bis[N-(1-naphthyl)-N-phenylamino]naphthalene-   4,4′-Bis[N-(9-anthryl)-N-phenylamino]biphenyl-   4,4″-Bis[N-(1-anthryl)-N-phenylamino]-p-terphenyl-   4,4′-Bis[N-(2-phenanthryl)-N-phenylamino]biphenyl-   4,4′-Bis[N-(8-fluoranthenyl)-N-phenylamino]biphenyl-   4,4′-Bis[N-(2-pyrenyl)-N-phenylamino]biphenyl-   4,4′-Bis[N-(2-naphthacenyl)-N-phenylamino]biphenyl-   4,4′-Bis[N-(2-perylenyl)-N-phenylamino]biphenyl-   4,4′-Bis[N-(1-coronenyl)-N-phenylamino]biphenyl-   2,6-Bis(di-p-tolylamino)naphthalene-   2,6-Bis[di-(1-naphthyl)amino]naphthalene-   2,6-Bis[N-(1-naphthyl)-N-(2-naphthyl)amino]naphthalene-   N,N,N′,N′-Tetra(2-naphthyl)-4,4″-diamino-p-terphenyl-   4,4′-Bis{N-phenyl-N-[4-(1-naphthyl)-phenyl]amino}biphenyl-   4,4′-Bis[N-phenyl-N-(2-pyrenyl)amino]biphenyl-   2,6-Bis[N,N-di(2-naphthyl)amine]fluorene-   1,5-Bis[N-(1-naphthyl)-N-phenylamino]naphthalene

Another class of useful hole-transporting materials includes polycyclicaromatic compounds as described in EP 1 009 041. In addition, polymerichole-transporting materials can be used such as poly(N-vinylcarbazole)(PVK), polythiophenes, polypyrrole, polyaniline, and copolymers such aspoly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) also calledPEDOT/PSS.

Light-Emitting Layer (LEL)

As more fully described in U.S. Pat. Nos. 4,769,292 and 5,935,721, thelight-emitting layer (LEL) 14 (14R, 14G, 14B) and 54R, 54G, 54B of theorganic EL display includes a luminescent or fluorescent material whereelectroluminescence is produced as a result of electron-hole pairrecombination in this region. The light-emitting layer can be comprisedof a single material, but more commonly consists of at least one hostmaterial doped with a guest compound or compounds (a dopant or dopants)where light emission comes primarily from the dopant and can be of anycolor. The host materials in the light-emitting layer can be anelectron-transporting material, as defined below, a hole-transportingmaterial, as defined above, or another material or combination ofmaterials that support hole-electron recombination. The dopant isusually chosen from highly fluorescent dyes, but phosphorescentcompounds, e.g., transition metal complexes as described in WO 98/55561,WO 00/18851, WO 00/57676, and WO 00/70655 are also useful. Dopants aretypically coated at 0.01 to 10% by weight into the host material.Polymeric materials such as polyfluorenes and polyvinylarylenes (e.g.,poly(p-phenylenevinylene), PPV) can also be used as the host material.In this case, small molecule dopants can be molecularly dispersed intothe polymeric host, or the dopant could be added by copolymerizing aminor constituent into the host polymer.

An important relationship for choosing a dye as a dopant is a comparisonof the bandgap potential which is defined as the energy differencebetween the highest occupied molecular orbital and the lowest unoccupiedmolecular orbital of the molecule. For efficient energy transfer fromthe host to the dopant molecule, a necessary condition is that the bandgap of the dopant is smaller than that of the host material.

Host and emitting dopant molecules known to be of use include, but arenot limited to, those disclosed in U.S. Pat. Nos. 4,768,292; 5,141,671;5,150,006; 5,151,629; 5,405,709; 5,484,922; 5,593,788; 5,645,948;5,683,823; 5,755,999; 5,928,802; 5,935,720; 5,935,721; and 6,020,078.

Metal complexes of 8-hydroxyquinoline and similar derivatives (FormulaE) constitute one class of useful host compounds capable of supportingelectroluminescence, and are particularly suitable for light emission ofwavelengths longer than 500 nm, e.g., green, yellow, orange, and red.

wherein:

M represents a metal;

n is an integer of from 1 to 4; and

Z independently in each occurrence represents the atoms completing anucleus having at least two fused aromatic rings.

From the foregoing it is apparent that the metal can be monovalent,divalent, trivalent, or tetravalent metal. The metal can, for example,be an alkali metal, such as lithium, sodium, or potassium; an alkalineearth metal, such as magnesium or calcium; an earth metal, such aluminumor gallium, or a transition metal such as zinc or zirconium. Generallyany monovalent, divalent, trivalent, or tetravalent metal known to be auseful chelating metal can be employed.

Z completes a heterocyclic nucleus containing at least two fusedaromatic rings, at least one of which is an azole or azine ring.Additional rings, including both aliphatic and aromatic rings, can befused with the two required rings, if required. To avoid addingmolecular bulk without improving on function the number of ring atoms isusually maintained at 18 or less.

Illustrative of useful chelated oxinoid compounds are the following:

-   CO-1: Aluminum trisoxine [alias, tris(8-quinolinolato)aluminum(III)]-   CO-2: Magnesium bisoxine [alias, bis(8-quinolinolato)magnesium(II)]-   CO-3: Bis[benzo{f}-8-quinolinolato]zinc (II)-   CO-4:    Bis(2-methyl-8-quinolinolato)aluminum(III)-μ-oxo-bis(2-methyl-8-quinolinolato)aluminum(III)-   CO-5: Indium trisoxine [alias, tris(8-quinolinolato)indium]-   CO-6: Aluminum tris(5-methyloxine) [alias,    tris(5-methyl-8-quinolinolato)aluminum(III)]-   CO-7: Lithium oxine [alias, (8-quinolinolato)lithium(I)]-   CO-8: Gallium oxine [alias, tris(8-quinolinolato)gallium(III)]-   CO-9: Zirconium oxine [alias, tetra(8-quinolinolato)zirconium(IV)]

Derivatives of 9,10-di-(2-naphthyl)anthracene (Formula F) constitute oneclass of useful hosts capable of supporting electroluminescence, and areparticularly suitable for light emission of wavelengths longer than 400nm, e.g., blue, green, yellow, orange or red.

F

wherein R¹, R², R³, R⁴, R⁵, and R⁶ represent one or more substituents oneach ring where each substituent may be individually selected from thefollowing groups:

Group 1: hydrogen, alkenyl, alkyl, or cycloalkyl of from 1 to 24 carbonatoms;

Group 2: aryl or substituted aryl of from 5 to 20 carbon atoms;

Group 3: carbon atoms from 4 to 24 necessary to complete a fusedaromatic ring such as anthracenyl; pyrenyl, or perylenyl;

Group 4: heteroaryl or substituted heteroaryl of from 5 to 24 carbonatoms as necessary to complete a fused heteroaromatic ring of furyl,thienyl, pyridyl, quinolinyl or other heterocyclic systems;

Group 5: alkoxylamino, alkylamino, or arylamino of from 1 to 24 carbonatoms; and

Group 6: fluorine, chlorine, bromine or cyano.

Illustrative examples include 9,10-di-(2-naphthyl)anthracene and2-t-butyl-9,10-di-(2-naphthyl)anthracene. Other anthracene derivativescan be useful as a host in the LEL, including derivatives of9,10-bis[4-(2,2-diphenylethenyl)phenyl]anthracene.

Benzazole derivatives (Formula G) constitute another class of usefulhosts capable of supporting electroluminescence, and are particularlysuitable for light emission of wavelengths longer than 400 nm, e.g.,blue, green, yellow, orange or red.

where:

n is an integer of 3 to 8;

Z is O, NR or S;

R and R′ are individually hydrogen; alkyl of from 1 to 24 carbon atoms,for example, propyl, t-butyl, heptyl, and the like; aryl or hetero-atomsubstituted aryl of from 5 to 20 carbon atoms for example phenyl andnaphthyl, furyl, thienyl, pyridyl, quinolinyl and other heterocyclicsystems; or halo such as chloro, fluoro; or atoms necessary to completea fused aromatic ring; and there may be up to 4 R′ groups per benzazoleunit; and

L is a linkage unit consisting of alkyl, aryl, substituted alkyl, orsubstituted aryl, which conjugately or unconjugately connects themultiple benzazoles together.

An example of a useful benzazole is2,2′,2″-(1,3,5-phenylene)tris[1-phenyl-1H-benzimidazole].

Distyrylarylene derivatives as described in U.S. Pat. No. 5,121,029 arealso useful host material for the LEL.

Desirable fluorescent dopants include derivatives of anthracene,tetracene, xanthene, perylene, rubrene, coumarin, rhodamine,quinacridone, dicyanomethylenepyran compounds, thiopyran compounds,polymethine compounds, pyrilium and thiapyrilium compounds, fluorenederivatives, periflanthene derivatives, and carbostyryl compoundsillustrative examples of useful dopants include, but are not limited to,the following:

X R1 R2 L9 O H H L10 O H Methyl L11 O Methyl H L12 O Methyl Methyl L13 OH t-butyl L14 O t-butyl H L15 O t-butyl t-butyl L16 S H H L17 S H MethylL18 S Methyl H L19 S Methyl Methyl L20 S H t-butyl L21 S t-butyl H L22 St-butyl t-butyl

X R1 R2 L23 O H H L24 O H Methyl L25 O Methyl H L26 O Methyl Methyl L27O H t-butyl L28 O t-butyl H L29 O t-butyl t-butyl L30 S H H L31 S HMethyl L32 S Methyl H L33 S Methyl Methyl L34 S H t-butyl L35 S t-butylH L36 S t-butyl t-butyl

R R L37 phenyl L38 methyl L39 t-butyl L40 mesityl

R L41 phenyl L42 methyl L43 t-butyl L44 mesityl

Electron-Transporting Layer (ETL)

Preferred thin film-forming materials for use in forming theelectron-transporting layer 15 (55) of the organic EL display are metalchelated oxinoid compounds, including chelates of oxine itself (alsocommonly referred to as 8-quinolinol or 8-hydroxyquinoline). Suchcompounds help to inject and transport electrons and exhibit both highlevels of performance and are readily fabricated in the form of thinfilms. Exemplary of contemplated oxinoid compounds are those satisfyingstructural formula (E), previously described.

Other electron-transporting materials include various butadienederivatives as disclosed in U.S. Pat. No. 4,356,429 and variousheterocyclic optical brighteners as described in U.S. Pat. No.4,539,507. Benzazoles satisfying structural formula (G) are also usefulelectron-transporting materials.

Cathode(s)

When light emission is viewed solely through the anode(s), the commoncathode 56 or the cathodes 16 can be comprised of nearly any conductivematerial. Desirable materials have good film-forming properties toensure good contact with the underlying organic layer, promote electroninjection at low voltage, and have good stability. Useful cathodematerials often contain a low work function metal (<4.0 eV) or metalalloy. One preferred cathode material is comprised of a Mg:Ag alloywherein the percentage of silver is in the range of 1 to 20%, asdescribed in U.S. Pat. No. 4,885,221. Another suitable class of cathodematerials includes bilayers comprising a thin electron-injection layer(EIL) in contact with the organic layer (e.g., ETL) which is capped witha thicker layer of a conductive metal. Here, the EIL preferably includesa low work function metal or metal salt, and if so, the thicker cappinglayer does not need to have a low work function. One such cathode iscomprised of a thin layer of LiF followed by a thicker layer of Al asdescribed in U.S. Pat. No. 5,677,572. Other useful cathode material setsinclude, but are not limited to, those disclosed in U.S. Pat. Nos.5,059,861; 5,059,862, and 6,140,763.

When light emission is viewed through the cathode, the cathode must betransparent or nearly transparent. For such applications, metals must bethin or one must use transparent conductive oxides, or a combination ofthese materials. Optically transparent cathodes have been described inmore detail in U.S. Pat. No. 5,776,623. Cathode materials can bedeposited by evaporation, sputtering, or chemical vapor deposition. Whenneeded, patterning can be achieved through many well known methodsincluding, but not limited to, through-mask deposition, integral shadowmasking as described in U.S. Pat. No. 5,276,380 and EP 0 732 868, laserablation, and selective chemical vapor deposition.

Encapsulation

Most OLED devices and displays are sensitive to moisture or oxygen, orboth, so they are commonly sealed in an inert atmosphere such asnitrogen or argon, along with a desiccant such as alumina, bauxite,calcium sulfate, clays, silica gel, zeolites, alkaline metal oxides,alkaline earth metal oxides, sulfates, or metal halides andperchlorates. Methods for encapsulation and desiccation include, but arenot limited to, those described in U.S. Pat. No. 6,226,890. In addition,barrier layers such as SiOx, Teflon, and alternating inorganic/polymericlayers are known in the art for encapsulation.

The invention has been described in detail with particular reference tocertain preferred embodiments thereof, but it will be understood thatvariations and modifications can be effected within the spirit and scopeof the invention. For example, rather than using organic materials,inorganic materials can also be used in accordance with the presentinvention.

PARTS LIST

-   10 single-color or monochrome passive matrix OLED device or display-   10-3C three-color or full-color passive matrix OLED display-   11 OLED display substrate-   12 light-transmissive first electrodes or anodes-   13 organic hole-injecting and hole-transporting layer (HTL)-   14 organic light-emitting layer (LEL)-   14 a vaporizable organic material(s)-   14R organic red-light-emitting layer-   14G organic green-light-emitting layer-   14B organic blue-light-emitting layer-   15 organic electron-transporting layer (ETL)-   16 second electrodes or cathodes-   18 encapsulation or cover-   50-3C three-color or full-color active matrix OLED display-   51 OLED display substrate-   52 light-transmissive first electrode pads or anode pads-   53 organic hole-injecting and hole-transporting layer-   54R organic red-light-emitting layer-   54G organic green-light-emitting layer-   54B organic blue-light-emitting layer-   55 organic electron-transporting layer-   56 common second electrode or cathode-   61-1 transistors, capacitor, and electrical wiring (in subpixel 1;1)-   61-2 transistors, capacitor, and electrical wiring (in subpixel 1;2)-   61-3 transistors, capacitor, and electrical wiring (in subpixel 1;3)-   64 conductive wiring-   66 light-transmissive organic insulator layer-   68 organic insulator layer-   87 X-direction driving circuit-   88 Y-direction driving circuit-   100 OLED apparatus-   102 buffer hub-   103 unload station-   104 transfer hub-   105 connector port-   106 vacuum pump-   107 pumping port-   108 pressure gauge-   110 load station-   110C chamber-   110H housing-   111 carrier (for substrates or structures)-   130 vapor deposition station (organic HTL)-   140 vapor deposition station (organic LEL)-   140C chamber-   140H housing-   141 station valve-   142 station vacuum pump-   144 station pumping port-   145 throttle valve-   146 station pressure sensor-   147 inert gas supply-   148 conduit-   149 gas flow controller-   150 vapor deposition station (organic ETL)-   160 vapor deposition station (second electrodes)-   170 storage station-   180 encapsulation station-   210 lead screw drive motor-   211 lead screw shaft-   211 a shaft seal-   212 lead screw-   213 lead screw shaft termination bracket-   214 lead screw follower-   216 switch-   217 lead-   218 input terminal-   220 stepper motor for indexing in y-direction-   221 computer for indexing in y-direction-   222 drive shaft-   223 shaft seal-   224 shaft coupling-   225 glide shoe-   225R glide rail-   226 coupling lifter-   230 holder or mask frame-   232 alignment tab(s)-   233 alignment window(s)-   234 alignment detector-   235 optical window-   236 optical alignment axis-   238 shutter-   500 vapor deposition apparatus-   500M manifold-   500MA manifold assembly-   500MB manifold for providing blue light-emitting organic material    vapor-   500MG manifold for providing green light-emitting organic material    vapor-   500MR manifold for providing red light-emitting organic material    vapor-   500IGS inert gas supply-   500VS organic material vapor source-   500VS1 organic material vapor source-   500VS2 organic material vapor source-   500VS3 organic material vapor source-   500VS4 organic material vapor source-   500CM cylindrical tubular manifold-   500CM-1 modified cylindrical tubular manifold-   502 manifold housing-   504 structure or nozzle plate-   504C curved structure or curved nozzle plate-   504T structure or nozzle plate for two-dimensional nozzle array-   506 nozzles-   506B nozzles in manifold 500MB-   506G nozzles in manifold 500MG-   506R nozzles in manifold 500MR-   510 directed beam(s) of organic material vapor(s) and inert gas-   520 manifold heating element(s)-   530 thermally insulative manifold support-   532 gasket-   533 alignment mark(s) on nozzle plate (504)-   535 alignment mark(s) on cylindrical tubular manifold (500CM)-   536 cylindrical manifold housing-   537 slit-shaped aperture in cylindrical manifold housing (536)-   538 end cap-   539 end cap-   540 housing of vapor source (500VS)-   541 flange-   542 gasket-   543 bolt(s)-   544 source cover-   545 seal-   546 a lower vapor transport conduit-   546 b upper vapor transport conduit-   546 c common conduit for vapor transport and gas transport-   547 c common conduit for vapor transport from one vapor source and    for gas transport-   550 vaporization heater-   552 feedthrough-   554 feedthrough-   560 g gas flow control device-   560 v vapor flow control device-   562 gas shut-off valve-   564 inert gas preheater-   566 a lower gas transport conduit-   566 b upper gas transport conduit-   570 combiner-   600 heatable enclosure-   750 vaporization heater power supply-   750R regulator-   752 lead-   753 current meter-   754 lead-   ∝ angle subtending vapor stream issuing from nozzles (506)-   CL center line of line of nozzles-   D spacing between substrate (11;51) and nozzles (506)-   d inside dimension or diameter of nozzles (506)-   l length dimension of nozzles (506)-   EL organic electroluminescent or electroluminescence medium-   “F” forward motion of substrate-   “R” reverse or return motion of substrate-   “I” starting position of substrate-   “II” end position of forward motion and beginning position of    reverse motion of substrate-   pix pixel-   P_(c) reduced pressure in chamber (140C)-   P_(G) inert gas pressure in manifold (500M)-   P_(V) vapor pressure of organic material(s) in manifold (500M)-   P_(v)+P_(g) combined pressure in manifold (500M) of inert gas and    organic material vapor(s)-   s nozzle pitch or spacing between nozzles in a nozzle plate (504)-   T_(e) temperature within heatable enclosure (600)-   x motion in x-direction of substrate (11;51)-   y indexed motion in y-direction of substrate (11;51)-   m columns of nozzles (506) of two-dimensional array of nozzles    (504T)-   n rows of nozzles (506) of two-dimensional array of nozzles (504T)-   Xn X-direction signal lines where n is an integer-   Ym Y-direction signal lines where m is an integer-   Vddn power supply lines-   TSnm thin-film transistors for switching-   TCnm thin-film transistors for power control-   ELnm organic electroluminescent medium in each pixel or sub-pixel-   Cnm thin-film capacitors

1. A method of depositing in a pattern organic material onto an OLEDdisplay substrate, comprising: a) providing a manifold and an OLEDdisplay substrate in a chamber at reduced pressure and spaced relativeto each other; b) providing a structure sealingly covering one surfaceof the manifold, the structure including a plurality of nozzles withorifices, nozzles extending through the structure into the manifold, andthe nozzles being spaced from each other in correspondence with thepattern to be deposited onto the OLED display substrate; c) orientingthe OLED display substrate with respect to the nozzles in the structure;d) delivering vaporized organic materials into the manifold; and e)applying an inert gas under pressure into the manifold so that the inertgas provides a viscous gas flow through each of the nozzles, suchviscous gas flow transporting at least portions of the vaporized organicmaterials from the manifold through the nozzles to provide collimatedbeams of the inert gas and of the vaporized organic materials that exitthe nozzles smoothly in streamlines parallel to the walls of the orificeand projecting the collimated beams onto the OLED display substratethereby depositing organic material on the substrate.
 2. The method ofclaim 1 wherein step b) includes the steps of i) constructing thestructure from a material selected from the group consisting of metals,glass, quart, graphite and ceramics; ii) forming the plurality ofnozzles in the structure as nozzles defining a circular outline or apolygonal outline; and iii) spacing the nozzles from each othercorresponding to a first color-forming pattern of a first organiclight-emitting layer to be deposited on the OLED display substrate. 3.The method of claim 1 further including forming the plurality of nozzlesin a plate structure or in a tubular structure.
 4. The method of claim 1further including forming the plurality of nozzles in the structurealong a single center line, and providing relative motion between theOLED display substrate and the manifold during deposition of acolor-forming stripe pattern of an organic light-emitting layer on thesubstrate.
 5. The method of claim 1 further including forming theplurality of nozzles in the structure as a two-dimensional array ofnozzles in correspondence with selected pixel locations on the OLEDdisplay substrate for providing a pixelated pattern of an organiclight-emitting layer on the selected pixel locations of the substrate.6. The method of claim 1 wherein step a) includes spacing the OLEDdisplay substrate from at least one surface of the structure by adistance from 0.02 to 2.0 centimeter.
 7. The method of claim 1 whereinstep d) includes the steps of: i) providing at least first and secondvapor sources disposed outside of the chamber; ii) connecting each ofthe vapor sources to the manifold; iii) charging the first vapor sourcewith at least one vaporizable organic host material, and charging thesecond vapor source with at least one vaporizable organic dopantmaterial selected to cause emission of one of red, green, or blue lightfrom a pattern of an organic light-emitting layer of an operative OLEDdisplay; and iv) controllably heating the first and second vapor sourcesto a vaporization temperature which causes at least portions of theorganic materials charged into the vapor sources to vaporize, anddelivering such vaporized organic materials from the vapor sourcesthrough respectively corresponding connections into the manifold.
 8. Themethod of claim 7 further including heating surfaces of the vaporsources, surfaces of the connections, and surfaces of the manifold andthe structure to a temperature sufficient to prevent condensation oforganic material vapors on such surfaces.
 9. The method of claim 7further including controlling the delivering of vaporized organicmaterials into the manifold so that a selected vapor pressure ofvaporized organic materials is provided in the manifold.
 10. The methodof claim 1 further including the steps of: i) providing a source ofinert gas; ii) preheating the inert gas to a temperature sufficient toprevent condensation of vaporized organic materials in the manifold andin the nozzles of the structure; iii) controlling the pressure of thepreheated inert gas or controlling the flow of the preheated inert gas;and iv) applying the preheated and controlled inert gas into themanifold.
 11. The method of claim 10 further including controlling thepressure or the flow of the preheated inert gas.
 12. The method of claim1, wherein said nozzles have an inside dimension in a range from 10 to1000 micrometer, and a nozzle length dimension that is at least 5 timeslarger than said inside dimension.
 13. A method of depositing in apattern an organic layer onto an OLED display substrate, comprising thesteps of: a) providing a manifold and an OLED display substrate in achamber at reduced pressure and spaced relative to each other; b)providing a structure sealingly covering one surface of the manifold,the structure including a plurality of nozzles with orifices, thenozzles extending through the structure into the manifold, and thenozzles being spaced from each other in correspondence with the patternto be deposited onto the OLED display substrate; c) orienting the OLEDdisplay substrate with respect to the nozzles in the structure; d)vaporizing organic materials in the manifold; and e) applying an inertgas under pressure into the manifold so that the inert gas provides aviscous gas flow through each of the nozzles, such viscous gas flowtransporting at least portions of the vaporized organic materials fromthe manifold through the nozzles to provide collimated beams of theinert gas and of the vaporized organic materials that exit the nozzlessmoothly in streamlines parallel to the walls of the orifice andprojecting the collimated beams onto the OLED display substrate fordepositing a pattern of an organic layer on the substrate.
 14. A methodof depositing in a three-color pattern organic light-emitting layersonto an OLED display substrate, comprising the steps of: a) providing amanifold and an OLED display substrate in a chamber at reduced pressureand spaced relative to each other; b) providing a structure sealinglycovering at least one surface of the manifold, the structure including aplurality of nozzles with orifices, the nozzles extending through thestructure into the manifold, and the nozzles being spaced from eachother in correspondence with the pattern to be deposited onto the OLEDdisplay substrate; c) orienting the OLED display substrate with respectto the nozzles in the structure in correspondence with a first-colorpattern of a first organic light-emitting layer to be deposited on thesubstrate; d) delivering first-color forming vaporized organiclight-emitting materials into the manifold; e) applying an inert gasunder pressure into the manifold so that the inert gas provides aviscous gas flow through each of the nozzles, such viscous gas flowtransporting at least portions of the first-color forming vaporizedorganic light-emitting materials from the manifold through the nozzlesto provide collimated beams of the inert gas and of the first-colorforming vaporized organic light-emitting materials and projecting thecollimated beams onto the OLED display substrate for depositing afirst-color pattern of the first organic light-emitting layer on thesubstrate; f) reorienting the OLED display substrate with respect to thenozzles in the structure in correspondence with a second-color patternof a second organic light-emitting layer to be deposited on thesubstrate; g) delivering second-color forming vaporized organiclight-emitting materials into the manifold; h) applying an inert gasunder pressure into the manifold so that the inert gas provides aviscous gas flow through each of the nozzles, such viscous gas flowtransporting at least portions of the second-color forming vaporizedorganic light-emitting materials from the manifold through the nozzlesto provide collimated beams of the inert gas and of the second-colorforming vaporized organic light-emitting materials and projecting thecollimated beams onto the OLED display substrate for depositing asecond-color pattern of the second organic light-emitting layer on thesubstrate; i) reorienting the OLED display substrate with respect to thenozzles in the structure in correspondence with a third-color pattern ofa third organic light-emitting layer to be deposited on the substrate;j) delivering third-color forming vaporized organic light-emittingmaterials into the manifold; and k) applying an inert gas under pressureinto the manifold so that the inert gas provides a viscous gas flowthrough each of the nozzles, such viscous gas flow transporting at leastportions of the third-color forming vaporized organic light-emittingmaterials from the manifold through the nozzles to provide collimatedbeams of the inert gas and of the third-color forming vaporized organiclight-emitting materials and projecting the collimated beams onto theOLED display substrate for depositing a third-color pattern of the thirdorganic light-emitting layer on the substrate wherein the collimatedbeams of the inert gas and of the vaporized organic materials in each ofe), h), and k) exit the nozzles smoothly in streamlines parallel to thewalls of the orifice.
 15. The method of claim 14 wherein step b)includes the steps of: i) constructing the structure from a materialselected from the group consisting of metals, glass, quartz, graphiteand ceramics; ii) forming the plurality of nozzles in the structure asnozzles defining a circular outline or a polygonal outline; and iii)spacing the nozzles from each other corresponding to equal spacingsbetween the first-color pattern and the second-color pattern, andbetween the second-color pattern and the third-color pattern to provideequally spaced first, second, and third organic light-emitting layers,respectively, on the OLED display substrate.
 16. The method of claim 15wherein step ii) includes the step of forming the plurality of nozzlesin the structure with a nozzle inside dimension in a range from 10 to1000 micrometer, and a nozzle length dimension extending through thestructure which is at least 5 times larger than a selected nozzle insidedimension.
 17. The method of claim 16 further including forming theplurality of nozzles in a plate structure or in a tubular structure. 18.The method of claim 16 further including forming the plurality ofnozzles in the structure along a single center line, and providingrelative motion between the OLED display substrate and the manifoldduring deposition of three-color stripe patterns of the first second,and third organic light-emitting layers, respectively, on the substrate.19. The method of claim 16 further including forming the plurality ofnozzles in the structure as a two-dimensional array of nozzles incorrespondence with pixel locations on the OLED display substrate forproviding pixelated patterns of the first, second, and third organiclight-emitting layers, respectively, in corresponding pixel locations onthe substrate.
 20. The method of claim 14 further including forming theplurality of nozzles in the structure as a two-dimensional array ofnozzles in correspondence with selected pixel locations on the OLEDdisplay substrate for providing a pixelated pattern of an organiclight-emitting layer on the selected pixel locations of the substrate.21. The method of claim 14 wherein steps d), g), and j) include thesteps of: i) providing at least four vapor sources disposed outside ofthe chamber; ii) connecting each of the vapor sources to the manifold;iii) charging a first vapor source with at least one vaporizable organichost material, charging a second vapor source with at least onevaporizable first-color forming organic dopant material, charging athird vapor source with at least one vaporizable second-color formingorganic dopant material, and charging a fourth vapor source with atleast one vaporizable third-color forming organic dopant material; andiv) controllably heating the first and, in sequence, one of the second,third, or fourth vapor sources to a vaporization temperature whichcauses at least portions of the organic materials charged into the vaporsources to vaporize, and delivering such vaporized organic materialsfrom the vapor sources through respectively corresponding connectionsinto the manifold.
 22. The method of claim 21 further including heatingsurfaces of the vapor sources, surfaces of the connections, and surfacesof the manifold and the structure to a temperature sufficient to preventcondensation of organic material vapors on such surfaces.
 23. The methodof claim 21 further including selecting the first-color forming,second-color forming, and third-color forming organic dopant materialsto cause emission of red, green, and blue light, respectively, fromrespectively corresponding patterns of doped organic light-emittinglayers of an operative OLED display.
 24. The method of claim 21 furtherincluding controlling the delivering of vaporized organic light-emittingmaterials into the manifold so that a selected vapor pressure ofvaporized organic materials is provided in the manifold.
 25. The methodof claim 14 further including the steps of: i) providing a source ofinert gas; ii) preheating the inert gas to a temperature sufficient toprevent condensation of vaporized organic materials in the manifold andin the nozzles of the structure; iii) controlling the pressure of thepreheated inert gas or controlling the flow of the preheated inert gas;and iv) applying the preheated and controlled inert gas into themanifold.
 26. The method of claim 25 further including controlling thepressure or the flow of the preheated inert gas so that a pressure ofthe preheated inert gas in the manifold is higher than a vapor pressureof vaporized organic materials delivered into the manifold.
 27. A methodof concurrently depositing in a three-color pattern organiclight-emitting layers onto an OLED display substrate, comprising thesteps of: a) providing a manifold assembly and an OLED display substratein a chamber at reduced pressure and spaced relative to each other, themanifold assembly including a first manifold, a second manifold, and athird manifold; b) providing a separate structure sealingly covering atleast one surface of each one of the first, second, and third manifolds,each separate structure including a plurality of nozzles with orifices,the nozzles extending through each structure into a correspondingmanifold, and the nozzles in each separate structure being spaced fromeach other in correspondence with the three-color pattern to bedeposited onto the OLED display substrate; c) orienting the OLED displaysubstrate with respect to the nozzles in one of the separate structures;d) delivering concurrently first-color forming vaporized organiclight-emitting materials into the first manifold, second-color formingvaporized organic light-emitting materials into the second manifold, andthird-color forming vaporized organic light-emitting materials into thethird manifold assembly; and e) applying an inert gas under pressureconcurrently into each one of the first, second, and third manifolds sothat the inert gas provides a viscous gas flow through each of theplurality of nozzles in each of the separate structures, such viscousgas flow transporting concurrently at least portions of the first-colorforming, second-color forming, and third-color forming vaporized organiclight-emitting materials from a respectively corresponding manifoldthrough corresponding nozzles to provide collimated beams of the inertgas and of the first-color forming, second-color forming, andthird-color forming vaporized organic right-emitting materials that exitfrom the corresponding nozzles smoothly in streamlines parallel to thewalls of the orifice and projecting the collimated beams onto the OLEDdisplay substrate for concurrently depositing a three-color pattern onthe substrate.
 28. The method of claim 27 wherein step b) includes thesteps of: i) constructing each structure from a material selected fromthe group consisting of metals, glass, quartz, and ceramics; and ii)forming the plurality of nozzles in each structure as nozzles defining acircular outline or a polygonal outline.
 29. The method of claim 27wherein step d) includes the steps of: i) providing at least four vaporsources disposed outside of the chamber; ii) connecting a first andsecond vapor source to the first manifold of the manifold assembly,connecting the first and a third vapor source to the second manifold ofthe manifold assembly, and connecting the first and a fourth vaporsource to the third manifold of the manifold assembly; iii) charging thefirst vapor source with at least one vaporizable organic host material,charging the second vapor source with at least one vaporizablefirst-color forming organic dopant material, charging the third vaporsource with at least one vaporizable second-color forming organic dopantmaterial, and charging the fourth vapor source with at least onevaporizable third-color forming organic dopant material; and iv)controllably heating the first, second, third, and fourth vapor sourcesto a vaporization temperature which causes at least portions of theorganic materials charged into the vapor sources to vaporize, anddelivering such vaporized organic light-emitting materials from thevapor sources through a respectively corresponding connection into acorresponding manifold of the manifold assembly.
 30. The method of claim29 further including heating surfaces of the vapor sources, surfaces ofthe connections, and surfaces of the manifolds and the structures to atemperature sufficient to prevent condensation of organic materialvapors on such surfaces.
 31. The method of claim 29 further includingselecting the first-color forming, second-color forming, and third-colorforming organic dopant materials to cause emission of red, green, andblue light, respectively, from respectively corresponding patterns ofdoped organic light-emitting layers of an operative OLED display. 32.The method of claim 29 further including controlling the delivering ofvaporized organic light-emitting materials into each manifold so that aselected vapor pressure of vaporized organic light-emitting materials isprovided in each manifold.
 33. The method of claim 27 further includingthe steps of: i) providing a source of inert gas; ii) preheating theinert gas to a temperature sufficient to prevent condensation ofvaporized organic materials in each of the manifolds and in the nozzlesof each of the separate structures; iii) controlling the pressure of thepreheated inert gas or controlling the flow of the preheated inert gas;and iv) applying the preheated and controlled inert gas into each of themanifolds of the manifold assembly.
 34. The method of claim 33 furtherincluding controlling the pressure or the flow of the preheated inertgas so that a pressure of the preheated inert gas in each of themanifolds is higher than a vapor pressure of vaporized organic materialsdelivered into each manifold.
 35. The method of claim 27, wherein saidnozzles have an inside dimension in a range from 10 to 1000 micrometer,and a nozzle length dimension that is at least 5 times larger than saidinside dimension.
 36. The method of claim 35 further including formingthe plurality of nozzles in each structure along a single center line,and providing relative motion between the OLED display substrate and themanifold assembly during concurrent deposition of three-color stripepatterns of organic light-emitting layers on the substrate.
 37. A methodof depositing in a pattern vaporized material onto a surface,comprising: a) providing vaporized material in a manifold of reducedpressure; b) providing a structure sealingly covering at least onesurface of the manifold, the structure including a plurality of nozzleswith orifices, the nozzles extending through the structure into themanifold, and the nozzles being spaced from each other in correspondencewith the pattern to be deposited onto the surface; and c) applying aninert gas under pressure into the manifold so that the inert gasprovides a viscous gas flow through each of the nozzles, such viscousgas flow transporting at least portions of the vaporized material fromthe manifold through the nozzles to provide collimated beams of theinert gas and of the vaporized material that exit the nozzles smoothlyin streamlines parallel to the walls of the orifice and projecting thecollimated beams onto the at least one surface thereby depositingorganic material on the least one surface.
 38. The method of claim 37wherein step b) includes the steps of: i) constructing the structurefrom a material selected from the group consisting of metals, glass,quartz, and ceramics; ii) forming the plurality of nozzles in thestructure as nozzles defining a circular outline or a polygonal outline;and iii) spacing the nozzles from each other corresponding to a firstcolor-forming pattern of a first organic light-emitting layer to bedeposited on the OLED display substrate.
 39. The method of claim 37further including forming the plurality of nozzles in a plate structureor in a tubular structure.
 40. The method of claim 37, wherein saidnozzles have an inside dimension in a range from 10 to 1000 micrometer,and a nozzle length dimension that is at least 5 times larger than saidinside dimension.
 41. A method of simultaneously depositing in a patternorganic material onto an OLED display substrate, comprising: a)providing a plurality of manifolds relative to an OLED substrate in achamber at reduced pressure and spaced relative to each other; b)providing a structure sealingly covering at least one surface of each ofthe manifolds, the structure including a plurality of nozzles withorifices, the nozzles extending through the structure into the manifold,and the nozzles being spaced from each other in correspondence with thepattern to be deposited onto the OLED display substrate; c) providingdifferent vaporized organic materials into each manifold; and d)applying an inert gas under pressure into the manifolds so that theinert gas provides a viscous gas flow through each of the nozzles, suchviscous gas flow transporting at least portions of the vaporized organiclight-emitting materials from the manifolds through the nozzles toprovide collimated beams of the inert gas and of the vaporized organiclight-emitting materials that exit the nozzles smoothly in streamlinesparallel to the walls of the orifice and projecting the collimated beamsonto the OLED display substrate for depositing a pattern of an organiclight-emitting layer on the substrate.
 42. The method of claim 41,wherein said nozzles have an inside dimension in a range from 10 to 1000micrometer, and a nozzle length dimension that is at least 5 timeslarger than said inside dimension.